diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/util/MutableTreeModel.java b/ganttzk/src/main/java/org/zkoss/ganttz/util/MutableTreeModel.java
index 976d6eeac..569d5d293 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/util/MutableTreeModel.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/util/MutableTreeModel.java
@@ -328,4 +328,33 @@ public class MutableTreeModel<T> extends AbstractTreeModel {
         return getChildCount(node) > 0;
     }
 
+    public boolean contains(T parent, T child) {
+        Node<T> parentNode = find(parent);
+        Node<T> childNode = find(child);
+
+        if (parentNode != null && (childNode != null && childNode.getParent() != null)) {
+            return childNode.getParent().equals(parentNode);
+        }
+        return false;
+    }
+
+    public List<T> asList() {
+        List<T> result = new ArrayList<T>();
+        asList(getRoot(), result);
+        return result;
+    }
+
+    private void asList(T root, List<T> result) {
+        List<T> list = new ArrayList<T>();
+        for (int i = 0; i < getChildCount(root); i++) {
+            final T child = getChild(root, i);
+            list.add(child);
+            result.add(child);
+        }
+
+        for (T each: list) {
+            asList(each, result);
+        }
+    }
+
 }
diff --git a/ganttzk/src/test/java/org/zkoss/ganttz/util/MutableTreeModelTest.java b/ganttzk/src/test/java/org/zkoss/ganttz/util/MutableTreeModelTest.java
index 0035ca634..f75c0c5bc 100644
--- a/ganttzk/src/test/java/org/zkoss/ganttz/util/MutableTreeModelTest.java
+++ b/ganttzk/src/test/java/org/zkoss/ganttz/util/MutableTreeModelTest.java
@@ -440,6 +440,29 @@ public class MutableTreeModelTest {
         assertThat(model.getChild(model.getRoot(), 1), equalTo(prueba2));
     }
 
+    @Test
+    public void treeParentContainsChild() {
+        final MutableTreeModel<Prueba> model = MutableTreeModel
+            .create(Prueba.class);
+
+        Prueba parent = new Prueba();
+        model.addToRoot(parent);
+        Prueba child = new Prueba();
+        model.add(parent, child);
+        assertTrue(model.contains(parent, child));
+    }
+
+    @Test
+    public void treeParentDoesNotContainChild() {
+        final MutableTreeModel<Prueba> model = MutableTreeModel
+            .create(Prueba.class);
+
+        Prueba parent = new Prueba();
+        model.addToRoot(parent);
+        Prueba child = new Prueba();
+        assertFalse(model.contains(parent, child));
+    }
+
     private void checkIsValid(TreeDataEvent event, int type,
             Prueba expectedParent, int expectedPosition) {
         checkIsValid(event, type, expectedParent, expectedPosition,
@@ -461,4 +484,5 @@ public class MutableTreeModelTest {
         }
         return list.get(list.size() - 1);
     }
+
 }
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/materials/daos/IMaterialDAO.java b/navalplanner-business/src/main/java/org/navalplanner/business/materials/daos/IMaterialDAO.java
index f2855614f..1d7199390 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/materials/daos/IMaterialDAO.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/materials/daos/IMaterialDAO.java
@@ -21,17 +21,50 @@
 package org.navalplanner.business.materials.daos;
 
 import java.util.List;
+import java.util.Set;
 
 import org.navalplanner.business.common.daos.IGenericDAO;
 import org.navalplanner.business.materials.entities.Material;
+import org.navalplanner.business.materials.entities.MaterialCategory;
 
 /**
  * Interface IMaterialDAO
  *
  * @author Jacobo Aragunde Perez <jaragunde@igalia.com>
+ * @author Diego Pino Garcia <dpino@igalia.com>
  */
 public interface IMaterialDAO extends IGenericDAO<Material, Long> {
 
+    /**
+     * Searches {@link Material} by code and description (ilike matching) within
+     * categories
+     *
+     * @param text
+     * @param categories
+     * @return
+     */
+    List<Material> findMaterialsInCategories(String text,
+            Set<MaterialCategory> categories);
+
+    /**
+     * Searches {@link Material} by code and description (ilike matching) within
+     * category and its subcategories
+     *
+     * @param text
+     * @param materialCategory
+     * @return
+     */
+    List<Material> findMaterialsInCategoryAndSubCategories(String text,
+            MaterialCategory materialCategory);
+
     List<Material> getAll();
 
+    /**
+     * Returns all subcategories for materialCategory
+     *
+     * @param materialCategory
+     * @return
+     */
+    Set<MaterialCategory> getAllSubcategories(MaterialCategory materialCategory);
+
 }
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/materials/daos/MaterialDAO.java b/navalplanner-business/src/main/java/org/navalplanner/business/materials/daos/MaterialDAO.java
index 3a6b6a069..dd7b9c30c 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/materials/daos/MaterialDAO.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/materials/daos/MaterialDAO.java
@@ -20,10 +20,15 @@
 
 package org.navalplanner.business.materials.daos;
 
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
+import org.hibernate.Criteria;
+import org.hibernate.criterion.Restrictions;
 import org.navalplanner.business.common.daos.GenericDAOHibernate;
 import org.navalplanner.business.materials.entities.Material;
+import org.navalplanner.business.materials.entities.MaterialCategory;
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.context.annotation.Scope;
 import org.springframework.stereotype.Repository;
@@ -32,6 +37,7 @@ import org.springframework.stereotype.Repository;
  * DAO for {@link Material}
  *
  * @author Jacobo Aragunde Perez <jaragunde@igalia.com>
+ * @author Diego Pino Garcia <dpino@igalia.com>
  */
 @Repository
 @Scope(BeanDefinition.SCOPE_SINGLETON)
@@ -43,4 +49,44 @@ public class MaterialDAO extends GenericDAOHibernate<Material, Long> implements
         return list(Material.class);
     }
 
+    @Override
+    public List<Material> findMaterialsInCategoryAndSubCategories(String text,
+            MaterialCategory materialCategory) {
+        Set<MaterialCategory> materialCategories = new HashSet<MaterialCategory>();
+        if (materialCategory != null) {
+            materialCategories.add(materialCategory);
+            materialCategories.addAll(getAllSubcategories(materialCategory));
+        }
+        return findMaterialsInCategories(text, materialCategories);
+    }
+
+    @Override
+    public Set<MaterialCategory> getAllSubcategories(MaterialCategory materialCategory) {
+        Set<MaterialCategory> result = new HashSet<MaterialCategory>();
+        getAllSubcategories(result, materialCategory.getSubcategories());
+        return result;
+    }
+
+    private void getAllSubcategories(Set<MaterialCategory> materialCategories, Set<MaterialCategory> subcategories) {
+        for (MaterialCategory each: subcategories) {
+            materialCategories.add(each);
+            getAllSubcategories(materialCategories, each.getSubcategories());
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public List<Material> findMaterialsInCategories(String text,
+            Set<MaterialCategory> categories) {
+        Criteria criteria = this.getSession().createCriteria(Material.class);
+
+        text = "%" + text + "%";
+        criteria.add(Restrictions.or(Restrictions.ilike("code", text), Restrictions.eq("description", text)));
+        criteria.add(Restrictions.eq("disabled", false));
+        if (categories != null && !categories.isEmpty()) {
+            criteria.add(Restrictions.in("category", categories));
+        }
+        return criteria.list();
+    }
+
 }
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/Material.java b/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/Material.java
index 32fe0f98f..d07ec1382 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/Material.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/Material.java
@@ -40,7 +40,7 @@ public class Material extends BaseEntity implements Comparable {
 
     private String description;
 
-    private BigDecimal defaultUnitPrice;
+    private BigDecimal defaultUnitPrice = new BigDecimal(0);
 
     private UnitTypeEnum unitType;
 
@@ -113,7 +113,6 @@ public class Material extends BaseEntity implements Comparable {
     @Override
     public int compareTo(Object arg0) {
       final Material material = (Material) arg0;
-
       return code.compareTo(material.getCode());
     }
 
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/MaterialAssignment.java b/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/MaterialAssignment.java
new file mode 100644
index 000000000..a83a08292
--- /dev/null
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/MaterialAssignment.java
@@ -0,0 +1,139 @@
+/*
+ * This file is part of ###PROJECT_NAME###
+ *
+ * Copyright (C) 2009 Fundación para o Fomento da Calidade Industrial e
+ *                    Desenvolvemento Tecnolóxico de Galicia
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.navalplanner.business.materials.entities;
+
+import java.math.BigDecimal;
+import java.math.RoundingMode;
+import java.util.Date;
+
+import org.navalplanner.business.common.BaseEntity;
+import org.navalplanner.business.orders.entities.OrderElement;
+
+/**
+ *
+ * @author Diego Pino Garcia <dpino@igalia.com>
+ *
+ */
+public class MaterialAssignment extends BaseEntity implements Comparable {
+
+    Material material;
+
+    double units = 0;
+
+    BigDecimal unitPrice = new BigDecimal(0);
+
+    Date estimatedAvailability;
+
+    MaterialStatusEnum status = MaterialStatusEnum.PENDING;
+
+    OrderElement orderElement;
+
+    public static MaterialAssignment create() {
+        return BaseEntity.create(new MaterialAssignment());
+    }
+
+    protected MaterialAssignment() {
+
+    }
+
+    public static MaterialAssignment create(Material material) {
+        MaterialAssignment materialAssignment = create();
+        materialAssignment.setUnitPrice(material.getDefaultUnitPrice());
+        materialAssignment.setMaterial(material);
+        return materialAssignment;
+    }
+
+    public static MaterialAssignment create(MaterialAssignment materialAssignment) {
+        MaterialAssignment result = create();
+        result.setMaterial(materialAssignment.getMaterial());
+        result.setUnits(materialAssignment.getUnits());
+        result.setUnitPrice(materialAssignment.getUnitPrice());
+        result.setEstimatedAvailability(materialAssignment.getEstimatedAvailability());
+        result.setStatus(materialAssignment.getStatus());
+        return result;
+    }
+
+    public Material getMaterial() {
+        return material;
+    }
+
+    public void setMaterial(Material material) {
+        this.material = material;
+    }
+
+    public double getUnits() {
+        return units;
+    }
+
+    public void setUnits(double units) {
+        this.units = units;
+    }
+
+    public BigDecimal getUnitPrice() {
+        return unitPrice;
+    }
+
+    public void setUnitPrice(BigDecimal unitPrice) {
+        this.unitPrice = unitPrice;
+    }
+
+    public BigDecimal getTotalPrice() {
+        BigDecimal result = new BigDecimal(getUnits());
+        return result.multiply(getUnitPrice());
+    }
+
+    public void setTotalPrice(BigDecimal totalPrice) {
+        BigDecimal unitPrice = totalPrice;
+        unitPrice = unitPrice.divide(new BigDecimal(units), 3, RoundingMode.HALF_UP);
+        setUnitPrice(unitPrice);
+    }
+
+    public Date getEstimatedAvailability() {
+        return estimatedAvailability;
+    }
+
+    public void setEstimatedAvailability(Date estimatedAvailability) {
+        this.estimatedAvailability = estimatedAvailability;
+    }
+
+    public MaterialStatusEnum getStatus() {
+        return status;
+    }
+
+    public void setStatus(MaterialStatusEnum status) {
+        this.status = status;
+    }
+
+    public OrderElement getOrderElement() {
+        return orderElement;
+    }
+
+    public void setOrderElement(OrderElement orderElement) {
+        this.orderElement = orderElement;
+    }
+
+    @Override
+    public int compareTo(Object arg0) {
+        final MaterialAssignment materialAssignment = (MaterialAssignment) arg0;
+        return materialAssignment.getMaterial().compareTo(getMaterial());
+    }
+
+}
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/MaterialStatusEnum.java b/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/MaterialStatusEnum.java
new file mode 100644
index 000000000..2d1ffe05f
--- /dev/null
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/materials/entities/MaterialStatusEnum.java
@@ -0,0 +1,34 @@
+/*
+ * This file is part of ###PROJECT_NAME###
+ *
+ * Copyright (C) 2009 Fundación para o Fomento da Calidade Industrial e
+ *                    Desenvolvemento Tecnolóxico de Galicia
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.navalplanner.business.materials.entities;
+
+/**
+ *
+ * @author Diego Pino Garcia <dpino@igalia.com>
+ *
+ */
+public enum MaterialStatusEnum {
+    RECEIVED,
+    PENDING,
+    ORDERED,
+    PROCESSING,
+    CANCELED
+}
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderElement.java b/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderElement.java
index e8936012f..9be1977d2 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderElement.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderElement.java
@@ -42,6 +42,7 @@ import org.navalplanner.business.advance.exceptions.DuplicateAdvanceAssignmentFo
 import org.navalplanner.business.advance.exceptions.DuplicateValueTrueReportGlobalAdvanceException;
 import org.navalplanner.business.common.BaseEntity;
 import org.navalplanner.business.labels.entities.Label;
+import org.navalplanner.business.materials.entities.MaterialAssignment;
 import org.navalplanner.business.orders.entities.SchedulingState.ITypeChangedListener;
 import org.navalplanner.business.orders.entities.SchedulingState.Type;
 import org.navalplanner.business.orders.entities.TaskSource.TaskSourceSynchronization;
@@ -68,6 +69,8 @@ public abstract class OrderElement extends BaseEntity {
 
     protected Set<DirectAdvanceAssignment> directAdvanceAssignments = new HashSet<DirectAdvanceAssignment>();
 
+    protected Set<MaterialAssignment> materialAssignments = new HashSet<MaterialAssignment>();
+
     private Set<Label> labels = new HashSet<Label>();
 
     private String code;
@@ -262,6 +265,13 @@ public abstract class OrderElement extends BaseEntity {
 
     public void setInitDate(Date initDate) {
         this.initDate = initDate;
+        updateMaterialAssigmentsEstimatedAvailability(this.initDate);
+    }
+
+    private void updateMaterialAssigmentsEstimatedAvailability(Date estimatedAvailability) {
+        for (MaterialAssignment each: materialAssignments) {
+            each.setEstimatedAvailability(estimatedAvailability);
+        }
     }
 
     public Date getDeadline() {
@@ -644,4 +654,38 @@ public abstract class OrderElement extends BaseEntity {
             result.add(taskSource);
         }
     }
+
+    public Set<MaterialAssignment> getMaterialAssignments() {
+        return Collections.unmodifiableSet(materialAssignments);
+    }
+
+    public void addMaterialAssignment(MaterialAssignment materialAssignment) {
+        materialAssignments.add(materialAssignment);
+        materialAssignment.setOrderElement(this);
+    }
+
+    public void removeMaterialAssignment(MaterialAssignment materialAssignment) {
+        materialAssignments.remove(materialAssignment);
+    }
+
+    public double getTotalMaterialAssigmentUnits() {
+        double result = 0;
+
+        final Set<MaterialAssignment> materialAssigments = getMaterialAssignments();
+        for (MaterialAssignment each: materialAssigments) {
+            result += each.getUnits();
+        }
+        return result;
+    }
+
+    public BigDecimal getTotalMaterialAssigmentPrice() {
+        BigDecimal result = new BigDecimal(0);
+
+        final Set<MaterialAssignment> materialAssigments = getMaterialAssignments();
+        for (MaterialAssignment each: materialAssigments) {
+            result = result.add(each.getTotalPrice());
+        }
+        return result;
+    }
+
 }
diff --git a/navalplanner-business/src/main/resources/org/navalplanner/business/materials/entities/Materials.hbm.xml b/navalplanner-business/src/main/resources/org/navalplanner/business/materials/entities/Materials.hbm.xml
index 3fc44792c..a6ed47aa8 100644
--- a/navalplanner-business/src/main/resources/org/navalplanner/business/materials/entities/Materials.hbm.xml
+++ b/navalplanner-business/src/main/resources/org/navalplanner/business/materials/entities/Materials.hbm.xml
@@ -54,4 +54,31 @@
 
 </class>
 
+<!-- MaterialAssignment -->
+<class name="MaterialAssignment" table="MATERIAL_ASSIGMENT">
+    <id name="id" type="long" access="property">
+        <generator class="hilo">
+        <param name="max_lo">100</param>
+        </generator>
+    </id>
+    <version name="version" access="property" type="long" />
+
+    <property name="units" />
+
+    <property name="unitPrice" column="UNIT_PRICE" />
+
+    <property name="estimatedAvailability" column="ESTIMATED_AVAILABILITY" />
+
+    <property name="status">
+        <type name="org.hibernate.type.EnumType">
+            <param name="enumClass">org.navalplanner.business.materials.entities.MaterialStatusEnum</param>
+        </type>
+    </property>
+
+    <many-to-one name="orderElement" class="org.navalplanner.business.orders.entities.OrderElement" column="ORDER_ELEMENT_ID" />
+
+    <many-to-one name="material" class="Material" column="MATERIAL_ID" />
+
+</class>
+
 </hibernate-mapping>
diff --git a/navalplanner-business/src/main/resources/org/navalplanner/business/orders/entities/Orders.hbm.xml b/navalplanner-business/src/main/resources/org/navalplanner/business/orders/entities/Orders.hbm.xml
index e3b5baad3..5cb34723d 100644
--- a/navalplanner-business/src/main/resources/org/navalplanner/business/orders/entities/Orders.hbm.xml
+++ b/navalplanner-business/src/main/resources/org/navalplanner/business/orders/entities/Orders.hbm.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
-<hibernate-mapping package="org.navalplanner.business.orders.entities">
+<hibernate-mapping package="org.navalplanner.business.orders.entities" default-access="field">
     <class name="OrderElement" abstract="true">
         <id name="id" access="property" type="long">
             <generator class="hilo" >
@@ -37,6 +37,11 @@
             <one-to-many class="org.navalplanner.business.requirements.entities.CriterionRequirement"/>
         </set>
 
+        <set name="materialAssignments" cascade="all-delete-orphan" inverse="true">
+            <key column="ORDER_ELEMENT_ID" not-null="true" />
+            <one-to-many class="org.navalplanner.business.materials.entities.MaterialAssignment" />
+        </set>
+
         <!-- Inverse navigation from OrderElement to OrderLineGroup -->
         <many-to-one name="parent" access="field" cascade="all"/>
 
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/AssignedMaterialsToOrderElementController.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/AssignedMaterialsToOrderElementController.java
new file mode 100644
index 000000000..7fab34b7b
--- /dev/null
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/AssignedMaterialsToOrderElementController.java
@@ -0,0 +1,463 @@
+/*
+ * This file is part of ###PROJECT_NAME###
+ *
+ * Copyright (C) 2009 Fundación para o Fomento da Calidade Industrial e
+ *                    Desenvolvemento Tecnolóxico de Galicia
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.navalplanner.web.orders;
+
+import static org.navalplanner.web.I18nHelper._;
+
+import java.math.BigDecimal;
+import java.math.RoundingMode;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.apache.commons.logging.LogFactory;
+import org.navalplanner.business.materials.entities.Material;
+import org.navalplanner.business.materials.entities.MaterialAssignment;
+import org.navalplanner.business.materials.entities.MaterialCategory;
+import org.navalplanner.business.orders.entities.OrderElement;
+import org.navalplanner.web.common.Util;
+import org.zkoss.zk.ui.Component;
+import org.zkoss.zk.ui.Executions;
+import org.zkoss.zk.ui.SuspendNotAllowedException;
+import org.zkoss.zk.ui.util.GenericForwardComposer;
+import org.zkoss.zul.Doublebox;
+import org.zkoss.zul.Grid;
+import org.zkoss.zul.Label;
+import org.zkoss.zul.Listbox;
+import org.zkoss.zul.Listitem;
+import org.zkoss.zul.Messagebox;
+import org.zkoss.zul.Row;
+import org.zkoss.zul.SimpleListModel;
+import org.zkoss.zul.Tab;
+import org.zkoss.zul.Tree;
+import org.zkoss.zul.TreeModel;
+import org.zkoss.zul.Treecell;
+import org.zkoss.zul.Treeitem;
+import org.zkoss.zul.TreeitemRenderer;
+import org.zkoss.zul.Treerow;
+import org.zkoss.zul.api.Textbox;
+import org.zkoss.zul.impl.MessageboxDlg;
+
+/**
+ * Controller for showing {@link OrderElement} assigned {@link Material}
+ *
+ * @author Diego Pino García <dpino@igalia.com>
+ *
+ */
+public class AssignedMaterialsToOrderElementController extends
+        GenericForwardComposer {
+
+    private static final org.apache.commons.logging.Log LOG = LogFactory.getLog(AssignedMaterialsToOrderElementController.class);
+
+    private IAssignedMaterialsToOrderElementModel assignedMaterialsToOrderElementModel;
+
+    private Tree categoriesTree;
+
+    private Tree allCategoriesTree;
+
+    private Grid gridMaterials;
+
+    private Listbox lbFoundMaterials;
+
+    private Textbox txtSearchMaterial;
+
+    private Tab tbAssignedMaterials;
+
+    @Override
+    public void doAfterCompose(Component comp) throws Exception {
+        super.doAfterCompose(comp);
+        comp.setVariable("assignedMaterialsController", this, true);
+    }
+
+    public void openWindow(IOrderElementModel orderElementModel) {
+        assignedMaterialsToOrderElementModel.initEdit(orderElementModel);
+        prepareCategoriesTree();
+        prepareAllCategoriesTree();
+    }
+
+    /**
+     * Delay initialization of categories tree till user clicks on Materials tab
+     *
+     * Initializing model and renderer properties directly in ZUL resulted in calling the renderer
+     * more times than actually needed, resulting in noticeable lack of performance
+     */
+    private void prepareCategoriesTree() {
+        if (categoriesTree.getTreeitemRenderer() == null) {
+            categoriesTree.setTreeitemRenderer(getMaterialCategoryWithUnitsAndPriceRenderer());
+        }
+        categoriesTree.setModel(getMaterialCategories());
+    }
+
+    public TreeModel getMaterialCategories() {
+        return assignedMaterialsToOrderElementModel.getMaterialCategories();
+    }
+
+    private void prepareAllCategoriesTree() {
+        if (allCategoriesTree.getTreeitemRenderer() == null) {
+            allCategoriesTree.setTreeitemRenderer(getMaterialCategoryRenderer());
+        }
+        allCategoriesTree.setModel(getAllMaterialCategories());
+    }
+
+    public TreeModel getAllMaterialCategories() {
+        return assignedMaterialsToOrderElementModel.getAllMaterialCategories();
+    }
+
+    public double getTotalUnits() {
+        double result = 0;
+
+        final OrderElement orderElement = getOrderElement();
+        if (orderElement != null) {
+            result = orderElement.getTotalMaterialAssigmentUnits();
+        }
+        return result;
+    }
+
+    public BigDecimal getTotalPrice() {
+        BigDecimal result = new BigDecimal(0);
+
+        final OrderElement orderElement = getOrderElement();
+        if (orderElement != null) {
+            result = orderElement.getTotalMaterialAssigmentPrice();
+        }
+        return result.setScale(2, RoundingMode.HALF_UP);
+    }
+
+    private OrderElement getOrderElement() {
+        return assignedMaterialsToOrderElementModel.getOrderElement();
+    }
+
+    /**
+     * On selecting category, refresh {@link MaterialAssignment} associated with
+     * selected {@link MaterialCategory}
+     */
+    public void refreshMaterialAssigments() {
+        final List<MaterialAssignment> materials = getAssignedMaterials();
+        gridMaterials.setModel(new SimpleListModel(materials));
+        Util.reloadBindings(gridMaterials);
+    }
+
+    public List<MaterialAssignment> getAssignedMaterials() {
+        final Treeitem treeitem = categoriesTree.getSelectedItem();
+        return getAssignedMaterials(treeitem);
+    }
+
+    private List<MaterialAssignment> getAssignedMaterials(Treeitem treeitem) {
+        final MaterialCategory materialCategory = (treeitem != null) ? (MaterialCategory) treeitem.getValue() : null;
+        return getAssignedMaterials(materialCategory);
+    }
+
+    private List<MaterialAssignment> getAssignedMaterials(MaterialCategory materialCategory) {
+        return assignedMaterialsToOrderElementModel.getAssignedMaterials(materialCategory);
+    }
+
+    /**
+     * On changing total price, recalculate unit price and refresh categories tree
+     *
+     * @param row
+     */
+    public void updateTotalPrice(Row row) {
+        final MaterialAssignment materialAssignment = (MaterialAssignment) row
+                .getValue();
+        Doublebox totalPrice = (Doublebox) row.getChildren().get(5);
+        totalPrice.setValue(materialAssignment.getTotalPrice().doubleValue());
+        refreshTotalPriceAndTotalUnits(materialAssignment);
+    }
+
+    /**
+     * Refresh categoriesTree since it shows totalUnits and totalPrice as well
+     */
+    private void refreshTotalPriceAndTotalUnits(MaterialAssignment materialAssignment) {
+        final Treeitem item = findMaterialCategoryInTree(materialAssignment
+                .getMaterial().getCategory(), categoriesTree);
+        if (item != null) {
+            // Reload categoriesTree
+            categoriesTree.setModel(getMaterialCategories());
+        }
+    }
+
+    /**
+     * On changing unit price, recalculate total price and refresh categories tree
+     *
+     * @param row
+     */
+    public void updateUnitPrice(Row row) {
+        final MaterialAssignment materialAssignment = (MaterialAssignment) row.getValue();
+        Doublebox unitPrice = (Doublebox) row.getChildren().get(4);
+        unitPrice.setValue(materialAssignment.getUnitPrice().doubleValue());
+        refreshTotalPriceAndTotalUnits(materialAssignment);
+    }
+
+    /**
+     * Finds which {@link Treeitem} in tree is associated with category
+     *
+     * @param category
+     * @param tree
+     * @return
+     */
+    private Treeitem findMaterialCategoryInTree(MaterialCategory category, Tree tree) {
+        for (Iterator i = tree.getItems().iterator(); i.hasNext(); ) {
+            Treeitem treeitem = (Treeitem) i.next();
+            final MaterialCategory materialCategory = (MaterialCategory) treeitem.getValue();
+            if (category.equals(materialCategory)) {
+                return treeitem;
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Search materials on pressing search button
+     */
+    public void searchMaterials() {
+        final String text = txtSearchMaterial.getValue();
+        final MaterialCategory materialCategory = getSelectedCategory(allCategoriesTree);
+        assignedMaterialsToOrderElementModel.searchMaterials(text, materialCategory);
+        Util.reloadBindings(lbFoundMaterials);
+    }
+
+    /**
+     * Returns {@link MaterialCategory} associated with selected {@link Treeitem} in {@link Tree}
+     *
+     * @param tree
+     * @return
+     */
+    private MaterialCategory getSelectedCategory(Tree tree) {
+        final Treeitem treeitem = tree.getSelectedItem();
+        return (treeitem != null) ? (MaterialCategory) treeitem.getValue() : null;
+    }
+
+    /**
+     * Get materials found on latest search
+     *
+     * @return
+     */
+    public List<Material> getMatchingMaterials() {
+        return assignedMaterialsToOrderElementModel.getMatchingMaterials();
+    }
+
+    /**
+     * Assigns a list of selected {@link Material} to current {@link OrderElement}
+     */
+    public void assignSelectedMaterials() {
+        Set<Material> materials = getSelectedMaterials();
+        if (materials.isEmpty()) {
+            return;
+        }
+
+        for(Material each: materials) {
+            assignedMaterialsToOrderElementModel.addMaterialAssignment(each);
+        }
+
+        categoriesTree.clearSelection();
+        tbAssignedMaterials.setSelected(true);
+        lbFoundMaterials.clearSelection();
+        Util.reloadBindings(categoriesTree);
+        Util.reloadBindings(gridMaterials);
+    }
+
+    private Set<Material> getSelectedMaterials() {
+        Set<Material> result = new HashSet<Material>();
+
+        final Set<Listitem> listitems = lbFoundMaterials.getSelectedItems();
+        for (Listitem each: listitems) {
+            final Material material = (Material) each.getValue();
+            result.add(material);
+        }
+        return result;
+    }
+
+    public MaterialCategoryRenderer getMaterialCategoryRenderer() {
+        return new MaterialCategoryRenderer();
+    }
+
+    private class MaterialCategoryRenderer implements TreeitemRenderer {
+
+        /**
+         * Copied verbatim from org.zkoss.zul.Tree;
+         */
+        @Override
+        public void render(Treeitem ti, Object node) throws Exception {
+            final MaterialCategory materialCategory = (MaterialCategory) node;
+
+            Label lblName = new Label(materialCategory.getName());
+
+            Treerow tr = null;
+            ti.setValue(node);
+            if (ti.getTreerow() == null) {
+                tr = new Treerow();
+                tr.setParent(ti);
+                ti.setOpen(true); // Expand node
+            } else {
+                tr = ti.getTreerow();
+                tr.getChildren().clear();
+            }
+            // Add category name
+            Treecell cellName = new Treecell();
+            lblName.setParent(cellName);
+            cellName.setParent(tr);
+        }
+    }
+
+    public MaterialCategoryWithUnitsAndPriceRenderer getMaterialCategoryWithUnitsAndPriceRenderer() {
+        return new MaterialCategoryWithUnitsAndPriceRenderer();
+    }
+
+    private class MaterialCategoryWithUnitsAndPriceRenderer implements TreeitemRenderer {
+
+        /**
+         * Copied verbatim from org.zkoss.zul.Tree;
+         */
+        @Override
+        public void render(Treeitem ti, Object node) throws Exception {
+            final MaterialCategory materialCategory = (MaterialCategory) node;
+
+            Label lblName = new Label(materialCategory.getName());
+            Label lblUnits = new Label(new Double(getUnits(materialCategory)).toString());
+            Label lblPrice = new Label(getPrice(materialCategory).toString());
+
+            Treerow tr = null;
+            ti.setValue(node);
+            if (ti.getTreerow() == null) {
+                tr = new Treerow();
+                tr.setParent(ti);
+                ti.setOpen(true); // Expand node
+            } else {
+                tr = ti.getTreerow();
+                tr.getChildren().clear();
+            }
+            // Add category name
+            Treecell cellName = new Treecell();
+            lblName.setParent(cellName);
+            cellName.setParent(tr);
+
+            // Add total assigned material units in category
+            Treecell cellUnits = new Treecell();
+            lblUnits.setParent(cellUnits);
+            cellUnits.setParent(tr);
+
+            // Add total price for assigned materials in category
+            Treecell cellPrice = new Treecell();
+            lblPrice.setParent(cellPrice);
+            cellPrice.setParent(tr);
+        }
+
+        private double getUnits(MaterialCategory materialCategory) {
+            return assignedMaterialsToOrderElementModel.getUnits(materialCategory);
+        }
+
+        private BigDecimal getPrice(MaterialCategory materialCategory) {
+            return assignedMaterialsToOrderElementModel.getPrice(materialCategory);
+        }
+
+    }
+
+    /**
+     * On clicking remove {@link MaterialAssignment}, shows dialog for
+     * confirming removing selected element
+     *
+     * @param materialAssignment
+     */
+    public void showRemoveMaterialAssignmentDlg(MaterialAssignment materialAssignment) {
+        try {
+            int status = Messagebox.show(_("Delete item {0}. Are you sure?", materialAssignment.getMaterial().getCode()),
+                    _("Delete"), Messagebox.OK | Messagebox.CANCEL, Messagebox.QUESTION);
+            if (Messagebox.OK == status) {
+                removeMaterialAssignment(materialAssignment);
+            }
+        } catch (InterruptedException e) {
+            LOG.error(_("Error on showing delete materialAssignment: ", materialAssignment.getId()), e);
+        }
+    }
+
+    private void removeMaterialAssignment(MaterialAssignment materialAssignment) {
+        assignedMaterialsToOrderElementModel.removeMaterialAssignment(materialAssignment);
+        Util.reloadBindings(gridMaterials);
+        // Reload categoriesTree
+        categoriesTree.setModel(getMaterialCategories());
+    }
+
+    /**
+     * On clicking Split button, shows dialog for splitting selected
+     * {@link MaterialAssignment} into two
+     *
+     * @param materialAssignment
+     */
+    @SuppressWarnings("unchecked")
+    public void showSplitMaterialAssignmentDlg(MaterialAssignment materialAssignment) {
+        MessageboxDlg dialogSplitAssignment;
+
+        final String message = _("Create new material assignment out of material assignment {0}. Are you sure?",
+                materialAssignment.getMaterial().getCode());
+
+        Map args = new HashMap();
+        args.put("message", message);
+        args.put("title", _("Split new assignment"));
+        args.put("OK", Messagebox.OK);
+        args.put("CANCEL", Messagebox.CANCEL);
+        args.put("icon", Messagebox.QUESTION);
+
+        dialogSplitAssignment = (MessageboxDlg) Executions
+                .createComponents("/orders/_splitMaterialAssignmentDlg.zul",
+                        self, args);
+        Doublebox dbUnits = (Doublebox) dialogSplitAssignment.getFellowIfAny("dbUnits");
+        dbUnits.setValue(materialAssignment.getUnits());
+        try {
+            dialogSplitAssignment.doModal();
+            int status = dialogSplitAssignment.getResult();
+            if (Messagebox.OK == status) {
+                splitMaterialAssignment(materialAssignment, dbUnits.getValue());
+            }
+        } catch (SuspendNotAllowedException e) {
+            LOG.error(_("Error on splitting element: ", materialAssignment.getId()), e);
+        } catch (InterruptedException e) {
+            LOG.error(_("Error on splitting element: ", materialAssignment.getId()), e);
+        }
+    }
+
+    /**
+     * Creates a new {@link MaterialAssignment} out of materialAssignment, but
+     * setting its units attribute to units.
+     *
+     * materialAssignment passed as parameter decreases its units attribute in units
+     *
+     * @param materialAssignment
+     * @param units
+     */
+    private void splitMaterialAssignment(MaterialAssignment materialAssignment, double units) {
+        MaterialAssignment newMaterialAssignment = MaterialAssignment.create(materialAssignment);
+        double currentUnits = materialAssignment.getUnits();
+        if (units > currentUnits) {
+            units = currentUnits;
+            currentUnits = 0;
+        } else {
+            currentUnits -= units;
+        }
+        newMaterialAssignment.setUnits(units);
+        materialAssignment.setUnits(currentUnits);
+        assignedMaterialsToOrderElementModel.addMaterialAssignment(newMaterialAssignment);
+        Util.reloadBindings(gridMaterials);
+    }
+
+}
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/AssignedMaterialsToOrderElementModel.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/AssignedMaterialsToOrderElementModel.java
new file mode 100644
index 000000000..88a6a270d
--- /dev/null
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/AssignedMaterialsToOrderElementModel.java
@@ -0,0 +1,268 @@
+/*
+ * This file is part of ###PROJECT_NAME###
+ *
+ * Copyright (C) 2009 Fundación para o Fomento da Calidade Industrial e
+ *                    Desenvolvemento Tecnolóxico de Galicia
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.navalplanner.web.orders;
+
+import java.math.BigDecimal;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Set;
+
+import org.navalplanner.business.materials.daos.IMaterialCategoryDAO;
+import org.navalplanner.business.materials.daos.IMaterialDAO;
+import org.navalplanner.business.materials.entities.Material;
+import org.navalplanner.business.materials.entities.MaterialAssignment;
+import org.navalplanner.business.materials.entities.MaterialCategory;
+import org.navalplanner.business.orders.daos.IOrderElementDAO;
+import org.navalplanner.business.orders.entities.OrderElement;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.config.BeanDefinition;
+import org.springframework.context.annotation.Scope;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+import org.zkoss.ganttz.util.MutableTreeModel;
+import org.zkoss.zul.TreeModel;
+
+/**
+ * @author Diego Pino Garcia <dpino@igalia.com>
+ */
+@Service
+@Scope(BeanDefinition.SCOPE_PROTOTYPE)
+public class AssignedMaterialsToOrderElementModel implements
+        IAssignedMaterialsToOrderElementModel {
+
+    @Autowired
+    private IMaterialCategoryDAO categoryDAO;
+
+    @Autowired
+    private IMaterialDAO materialDAO;
+
+    @Autowired
+    private IOrderElementDAO orderElementDAO;
+
+    private IOrderElementModel orderElementModel;
+
+    private OrderElement orderElement;
+
+    private MutableTreeModel<MaterialCategory> materialCategories = MutableTreeModel
+            .create(MaterialCategory.class);
+
+    private MutableTreeModel<MaterialCategory> allMaterialCategories = MutableTreeModel
+            .create(MaterialCategory.class);
+
+    private List<Material> matchingMaterials = new ArrayList<Material>();
+
+    @Override
+    @Transactional(readOnly = true)
+    public void initEdit(IOrderElementModel orderElementModel) {
+        this.orderElementModel = orderElementModel;
+        this.orderElement = this.orderElementModel.getOrderElement();
+        orderElementDAO.reattach(this.orderElement);
+        materialCategories = MutableTreeModel.create(MaterialCategory.class);
+        initializeMaterialAssigments(this.orderElement.getMaterialAssignments());
+
+        // Initialize matching materials
+        matchingMaterials.clear();
+        matchingMaterials.addAll(materialDAO.getAll());
+        initializeMaterials(matchingMaterials);
+    }
+
+    private void initializeMaterialAssigments(
+            Set<MaterialAssignment> materialAssignments) {
+        for (MaterialAssignment each : materialAssignments) {
+            each.getStatus();
+            initializeMaterialCategory(each.getMaterial().getCategory());
+        }
+    }
+
+    @Transactional(readOnly = true)
+    private void initializeMaterialCategories(
+            Collection<MaterialCategory> materialCategories) {
+        for (MaterialCategory each : materialCategories) {
+            initializeMaterialCategory(each);
+        }
+    }
+
+    private void initializeMaterialCategory(MaterialCategory materialCategory) {
+        materialCategory.getName();
+        initializeMaterials(materialCategory.getMaterials());
+        initializeMaterialCategories(materialCategory.getSubcategories());
+    }
+
+    private void initializeMaterials(Collection<Material> materials) {
+        for (Material each : materials) {
+            initializeMaterial(each);
+        }
+    }
+
+    private void initializeMaterial(Material material) {
+        material.getDescription();
+        material.getCategory().getName();
+    }
+
+    @Override
+    public OrderElement getOrderElement() {
+        return orderElement;
+    }
+
+    @Override
+    @Transactional(readOnly = true)
+    public MutableTreeModel<MaterialCategory> getMaterialCategories() {
+        if (orderElement != null && materialCategories.isEmpty()) {
+            feedTree(materialCategories, orderElement.getMaterialAssignments());
+            initializeMaterialCategories(materialCategories.asList());
+        }
+        return materialCategories;
+    }
+
+    private void feedTree(MutableTreeModel<MaterialCategory> tree,
+            Set<MaterialAssignment> materialAssignments) {
+        for (MaterialAssignment each : materialAssignments) {
+            final Material material = (Material) each.getMaterial();
+            addCategory(tree, material.getCategory());
+        }
+    }
+
+    /**
+     * Adds category to treeModel
+     *
+     * If category.parent is not in treeModel add it to treeModel recursively.
+     *
+     */
+    private void addCategory(
+            MutableTreeModel<MaterialCategory> materialCategories,
+            MaterialCategory materialCategory) {
+
+        categoryDAO.reattach(materialCategory);
+        final MaterialCategory parent = materialCategory.getParent();
+        if (parent == null) {
+            if (!materialCategories.contains(parent, materialCategory)) {
+                materialCategories.addToRoot(materialCategory);
+            }
+        } else {
+            if (!materialCategories.contains(parent, materialCategory)) {
+                addCategory(materialCategories, parent);
+                materialCategories.add(parent, materialCategory);
+            }
+        }
+    }
+
+    @Override
+    @Transactional(readOnly = true)
+    public TreeModel getAllMaterialCategories() {
+        if (allMaterialCategories.isEmpty()) {
+            feedTree(allMaterialCategories, categoryDAO.getAll());
+            initializeMaterialCategories(allMaterialCategories.asList());
+        }
+        return allMaterialCategories;
+    }
+
+    private void feedTree(MutableTreeModel<MaterialCategory> tree,
+            List<MaterialCategory> materialCategories) {
+        for (MaterialCategory each : materialCategories) {
+            addCategory(tree, each);
+        }
+    }
+
+    @Override
+    public List<MaterialAssignment> getAssignedMaterials(
+            MaterialCategory materialCategory) {
+        List<MaterialAssignment> result = new ArrayList<MaterialAssignment>();
+        if (orderElement != null) {
+            for (MaterialAssignment materialAssigment : orderElement
+                    .getMaterialAssignments()) {
+                final Material material = materialAssigment.getMaterial();
+                if (materialCategory == null
+                        || materialCategory.equals(material.getCategory())) {
+                    result.add(materialAssigment);
+                }
+            }
+        }
+        return result;
+    }
+
+    @Override
+    @Transactional(readOnly = true)
+    public void searchMaterials(String text, MaterialCategory materialCategory) {
+        matchingMaterials = materialDAO
+                .findMaterialsInCategoryAndSubCategories(text, materialCategory);
+        initializeMaterials(matchingMaterials);
+    }
+
+    @Override
+    public List<Material> getMatchingMaterials() {
+        return matchingMaterials;
+    }
+
+    @Override
+    @Transactional(readOnly = true)
+    public void addMaterialAssignment(Material material) {
+        MaterialAssignment materialAssigment = MaterialAssignment
+                .create(material);
+        materialAssigment.setEstimatedAvailability(orderElement.getInitDate());
+        addMaterialAssignment(materialAssigment);
+    }
+
+    @Override
+    @Transactional(readOnly = true)
+    public void addMaterialAssignment(MaterialAssignment materialAssignment) {
+        orderElement.addMaterialAssignment(materialAssignment);
+        // Add material category to materialCategories tree
+        final MaterialCategory materialCategory = materialAssignment.getMaterial().getCategory();
+        addCategory(materialCategories, materialCategory);
+    }
+
+    @Override
+    public void removeMaterialAssignment(MaterialAssignment materialAssignment) {
+        orderElement.removeMaterialAssignment(materialAssignment);
+    }
+
+    @Override
+    public double getUnits(MaterialCategory materialCategory) {
+        double result = 0;
+        if (orderElement != null) {
+            for (MaterialAssignment materialAssignment : orderElement
+                    .getMaterialAssignments()) {
+                final Material material = materialAssignment.getMaterial();
+                if (materialCategory.equals(material.getCategory())) {
+                    result += materialAssignment.getUnits();
+                }
+            }
+        }
+        return result;
+    }
+
+    @Override
+    public BigDecimal getPrice(MaterialCategory materialCategory) {
+        BigDecimal result = new BigDecimal(0);
+        if (orderElement != null) {
+            for (MaterialAssignment materialAssignment : orderElement
+                    .getMaterialAssignments()) {
+                final Material material = materialAssignment.getMaterial();
+                if (materialCategory.equals(material.getCategory())) {
+                    result = result.add(materialAssignment.getTotalPrice());
+                }
+            }
+        }
+        return result;
+    }
+
+}
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/IAssignedMaterialsToOrderElementModel.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/IAssignedMaterialsToOrderElementModel.java
new file mode 100644
index 000000000..d62940ac7
--- /dev/null
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/IAssignedMaterialsToOrderElementModel.java
@@ -0,0 +1,102 @@
+/*
+ * This file is part of ###PROJECT_NAME###
+ *
+ * Copyright (C) 2009 Fundación para o Fomento da Calidade Industrial e
+ *                    Desenvolvemento Tecnolóxico de Galicia
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.navalplanner.web.orders;
+
+import java.math.BigDecimal;
+import java.util.List;
+
+import org.navalplanner.business.materials.entities.Material;
+import org.navalplanner.business.materials.entities.MaterialAssignment;
+import org.navalplanner.business.materials.entities.MaterialCategory;
+import org.navalplanner.business.orders.entities.OrderElement;
+import org.zkoss.zul.TreeModel;
+
+
+/**
+ * @author Diego Pino Garcia <dpino@igalia.com>
+ */
+public interface IAssignedMaterialsToOrderElementModel {
+
+    /**
+     * Add a new {@link MaterialAssignment} out of {@link Material}
+     *
+     * @param each
+     */
+    void addMaterialAssignment(Material material);
+
+    /**
+     * Add a new {@link MaterialAssignment} out of existing {@link MaterialAssignment}
+     *
+     * @param materialAssignment
+     */
+    void addMaterialAssignment(MaterialAssignment materialAssignment);
+
+    TreeModel getAllMaterialCategories();
+
+    List<MaterialAssignment> getAssignedMaterials(MaterialCategory materialCategory);
+
+    /**
+     * Returns list of {@link Material} found after executing latest search
+     *
+     * @return
+     */
+    List<Material> getMatchingMaterials();
+
+    /**
+     * Get list of {@link MaterialCategory} assigned to current {@link OrderElement}
+     *
+     * @return
+     */
+    TreeModel getMaterialCategories();
+
+    OrderElement getOrderElement();
+
+    /**
+     * Calculates sum of price for all {@link MaterialAssignment} which belong
+     * to {@link MaterialCategory}
+     *
+     * @param materialCategory
+     * @return
+     */
+    BigDecimal getPrice(MaterialCategory materialCategory);
+
+    /**
+     * Calculates sum of units for all {@link MaterialAssignment} which belong
+     * to {@link MaterialCategory}
+     *
+     * @param materialCategory
+     * @return
+     */
+    double getUnits(MaterialCategory materialCategory);
+
+    void initEdit(IOrderElementModel orderElementModel);
+
+    void removeMaterialAssignment(MaterialAssignment materialAssignment);
+
+    /**
+     * Searches materials in categories and its subcategories by code and
+     * description
+     *
+     * @param code
+     * @param materialCategory
+     */
+    void searchMaterials(String text, MaterialCategory materialCategory);
+}
\ No newline at end of file
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderCRUDController.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderCRUDController.java
index 808c801ec..6e7d78d48 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderCRUDController.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderCRUDController.java
@@ -115,12 +115,14 @@ public class OrderCRUDController extends GenericForwardComposer {
         OrderElementController orderElementController = new OrderElementController();
         orderElementController.doAfterCompose(comp
                 .getFellow("editOrderElement"));
+
         setupOrderElementTreeController(comp, orderElementController);
         setupDetailsOrderElementController(comp);
         setupAsignedHoursToOrderElementController(comp);
         setupManageOrderElementAdvancesController(comp);
         setupAssignedLabelsToOrderElementController(comp);
         setupAssignedCriterionRequirementsToOrderElementController(comp);
+        setupAssignedMaterialsToOrderElementController(comp);
     }
 
     private void setupOrderElementTreeController(Component comp,
@@ -178,6 +180,16 @@ public class OrderCRUDController extends GenericForwardComposer {
                 .getVariable("assignedCriterionRequirementController", true);
     }
 
+    private AssignedMaterialsToOrderElementController assignedMaterialsController;
+
+    private void setupAssignedMaterialsToOrderElementController(
+            Component comp) throws Exception {
+        Component orderElementMaterials = editWindow
+                .getFellowIfAny("orderElementMaterials");
+        assignedMaterialsController = (AssignedMaterialsToOrderElementController) orderElementMaterials
+                .getVariable("assignedMaterialsController", true);
+    }
+
     public List<Order> getOrders() {
         return orderModel.getOrders();
     }
@@ -315,6 +327,7 @@ public class OrderCRUDController extends GenericForwardComposer {
         manageOrderElementAdvancesController.openWindow(orderElementModel);
         assignedLabelsController.openWindow(orderElementModel);
         assignedCriterionRequirementController.openWindow(orderElementModel);
+        assignedMaterialsController.openWindow(orderElementModel);
     }
 
     private void clearEditWindow() {
diff --git a/navalplanner-webapp/src/main/resources/metainfo/zk/lang-addon.xml b/navalplanner-webapp/src/main/resources/metainfo/zk/lang-addon.xml
index b219c6e8e..2c616faab 100755
--- a/navalplanner-webapp/src/main/resources/metainfo/zk/lang-addon.xml
+++ b/navalplanner-webapp/src/main/resources/metainfo/zk/lang-addon.xml
@@ -40,7 +40,7 @@
         <component-class>org.navalplanner.web.common.components.NewDataSortableColumn</component-class>
         <extends>column</extends>
     </component>
-    
+
     <component>
         <component-name>schedulingStateToggler</component-name>
         <component-class>org.navalplanner.web.orders.SchedulingStateToggler</component-class>
@@ -61,4 +61,13 @@
         </annotation>
     </component>
 
+    <component>
+        <component-name>doublebox</component-name>
+            <extends>doublebox</extends>
+            <property>
+                <property-name>format</property-name>
+                <property-value>###,##0.00####</property-value>
+            </property>
+    </component>
+
 </language-addon>
diff --git a/navalplanner-webapp/src/main/webapp/orders/_edition.zul b/navalplanner-webapp/src/main/webapp/orders/_edition.zul
index 33b033755..d87c34251 100644
--- a/navalplanner-webapp/src/main/webapp/orders/_edition.zul
+++ b/navalplanner-webapp/src/main/webapp/orders/_edition.zul
@@ -24,6 +24,8 @@
 <?component name="listOrderElementAdvances" inline="true" macroURI="_listOrderElementAdvances.zul"?>
 <?component name="listOrderElementLabels" inline="true" macroURI="_listOrderElementLabels.zul"?>
 <?component name="listOrderElementCriterionRequirements" inline="true" macroURI="_listOrderElementCriterionRequirements.zul"?>
+<?component name="listOrderElementMaterials" inline="true" macroURI="_listOrderElementMaterials.zul"?>
+
 <window id="${arg.top_id}">
     <tabbox>
         <tabs>
@@ -35,6 +37,7 @@
             <tab label="${i18n:_('Label')}" />
             <tab id="tabRequirements" label="${i18n:_('Criterion Requirement')}"
                  onClick = "controller.reloadHoursGroupOrder();"/>
+            <tab label="${i18n:_('Materials')}" />
         </tabs>
         <tabpanels>
             <tabpanel>
@@ -111,6 +114,9 @@
             <tabpanel>
                 <listOrderElementCriterionRequirements id="orderElementCriterionRequirements"/>
             </tabpanel>
+            <tabpanel>
+                <listOrderElementMaterials id="orderElementMaterials"/>
+            </tabpanel>
         </tabpanels>
     </tabbox>
     <hbox>
diff --git a/navalplanner-webapp/src/main/webapp/orders/_listOrderElementMaterials.zul b/navalplanner-webapp/src/main/webapp/orders/_listOrderElementMaterials.zul
new file mode 100644
index 000000000..3d189cb33
--- /dev/null
+++ b/navalplanner-webapp/src/main/webapp/orders/_listOrderElementMaterials.zul
@@ -0,0 +1,180 @@
+<!--
+  This file is part of ###PROJECT_NAME###
+
+  Copyright (C) 2009 Fundación para o Fomento da Calidade Industrial e
+                     Desenvolvemento Tecnolóxico de Galicia
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU Affero General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU Affero General Public License for more details.
+
+  You should have received a copy of the GNU Affero General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<vbox id="${arg.id}"
+    apply="org.navalplanner.web.orders.AssignedMaterialsToOrderElementController" >
+
+    <zscript>
+        Object[] unitTypes = org.navalplanner.business.materials.entities.UnitTypeEnum
+            .values();
+        Object[] materialStatus = org.navalplanner.business.materials.entities.MaterialStatusEnum
+            .values();
+    </zscript>
+
+    <tabbox mold="accordion-lite">
+        <tabs>
+            <tab id="tbAssignedMaterials" label="${i18n:_('Materials')}" image="common/img/ico_bajar.png"/>
+            <tab label="${i18n:_('Material search')}" image="common/img/ico_bajar.png"/>
+        </tabs>
+        <tabpanels>
+            <tabpanel>
+                <hbox>
+                    <!-- Categories  -->
+                    <vbox>
+                        <panel title="${i18n:_('Categories')}" border="normal">
+                            <panelchildren>
+                                <toolbarbutton style="text-decoration: none" label="${i18n:_('Unselect')}" onClick="categoriesTree.clearSelection()" />
+                                <tree id="categoriesTree"
+                                        fixedLayout="false"
+                                        width="280px" rows="10" vflex="true" multiple="false"
+                                        onSelect="assignedMaterialsController.refreshMaterialAssigments()">
+                                    <treecols>
+                                        <treecol label="Name" />
+                                        <treecol label="Units" width="50px" />
+                                        <treecol label="Price" width="50px" />
+                                    </treecols>
+                                </tree>
+                            </panelchildren>
+                        </panel>
+                    </vbox>
+
+                    <!-- Materials -->
+                    <vbox>
+                        <panel title="${i18n:_('Materials')}"
+                            border="normal">
+                            <panelchildren>
+                                <newdatasortablegrid id="gridMaterials"
+                                    fixedLayout="false"
+                                    model="@{assignedMaterialsController.assignedMaterials}">
+                                    <columns>
+                                        <newdatasortablecolumn label="${i18n:_('Code')}" />
+                                        <newdatasortablecolumn label="${i18n:_('Date')}" />
+                                        <newdatasortablecolumn label="${i18n:_('Units')}" />
+                                        <newdatasortablecolumn label="${i18n:_('Unit type')}" />
+                                        <newdatasortablecolumn label="${i18n:_('Unit price')}" />
+                                        <newdatasortablecolumn label="${i18n:_('Total price')}" />
+                                        <newdatasortablecolumn label="${i18n:_('Category')}" />
+                                        <newdatasortablecolumn label="${i18n:_('Status')}" />
+                                        <newdatasortablecolumn label="" />
+                                    </columns>
+                                    <rows>
+                                        <row self="@{each='assignedMaterial'}" value="@{assignedMaterial}">
+                                            <textbox value="@{assignedMaterial.material.code}"
+                                                constraint="no empty:${i18n:_('cannot be null or empty')}"
+                                                readonly="true" />
+                                            <datebox value="@{assignedMaterial.estimatedAvailability}" />
+                                            <doublebox value="@{assignedMaterial.units}"
+                                                onChange="assignedMaterialsController.updateTotalPrice(self.parent)" />
+                                            <listbox mold="select" model="@{unitTypes}"
+                                                selectedItem="@{assignedMaterial.material.unitType}" disabled="true" />
+                                            <doublebox value="@{assignedMaterial.unitPrice}"
+                                                onChange="assignedMaterialsController.updateTotalPrice(self.parent)" />
+                                            <doublebox value="@{assignedMaterial.totalPrice}"
+                                                onChange="assignedMaterialsController.updateUnitPrice(self.parent)" />
+                                            <listbox mold="select" model="@{materialStatus}"
+                                                selectedItem="@{assignedMaterial.status}"/>
+                                            <label value="@{assignedMaterial.material.category.name}" width="150px" />
+                                            <hbox>
+                                                <button sclass="icono"
+                                                    image="/common/img/ico_borrar1.png"
+                                                    hoverImage="/common/img/ico_borrar.png"
+                                                    tooltiptext="${i18n:_('Delete')}"
+                                                    onClick="assignedMaterialsController.showRemoveMaterialAssignmentDlg(self.parent.parent.value)">
+                                                </button>
+                                                <button label="${i18n:_('Split')}"
+                                                    tooltiptext="${i18n:_('Split assignment')}"
+                                                    onClick="assignedMaterialsController.showSplitMaterialAssignmentDlg(self.parent.parent.value)">
+                                                </button>
+                                            </hbox>
+                                        </row>
+                                    </rows>
+                                </newdatasortablegrid>
+                            </panelchildren>
+                        </panel>
+                    </vbox>
+                </hbox>
+            </tabpanel>
+
+            <tabpanel>
+                <!-- Material search -->
+                <hbox>
+                    <!-- Categories  -->
+                    <vbox>
+                        <panel title="${i18n:_('Categories')}" border="normal">
+                            <panelchildren>
+                                <toolbarbutton style="text-decoration: none" label="${i18n:_('Unselect')}" onClick="allCategoriesTree.clearSelection()" />
+                                <tree id="allCategoriesTree"
+                                        width="280px" rows="10" vflex="true" multiple="false">
+                                    <treecols>
+                                        <treecol label="Name" />
+                                    </treecols>
+                                </tree>
+                            </panelchildren>
+                        </panel>
+                    </vbox>
+
+                    <vbox>
+
+                        <!-- Found materials -->
+                        <panel title="${i18n:_('Materials')}" border="normal">
+                            <panelchildren>
+
+                                <!-- Search textbox -->
+                                <hbox>
+                                    <textbox id="txtSearchMaterial" width="250px" style="margin-top: 5px" />
+                                    <button label="${i18n:_('Search')}" style="margin-bottom: 5px"
+                                        onClick="assignedMaterialsController.searchMaterials()"/>
+                                    <button label="${i18n:_('Assign')}"
+                                        onClick="assignedMaterialsController.assignSelectedMaterials()" />
+                                </hbox>
+
+                                <listbox id="lbFoundMaterials"
+                                    fixedLayout="true"
+                                    model="@{assignedMaterialsController.matchingMaterials}">
+                                    <listhead sizable="true">
+                                        <listheader label="${i18n:_('Code')}" />
+                                        <listheader label="${i18n:_('Name')}" />
+                                        <listheader label="${i18n:_('Unit type')}" />
+                                        <listheader label="${i18n:_('Unit price')}" />
+                                        <listheader label="${i18n:_('Category')}" />
+                                    </listhead>
+                                    <listitem self="@{each='material'}" value="@{material}">
+                                        <listcell label="@{material.code}" />
+                                        <listcell label="@{material.description}" />
+                                        <listcell>
+                                            <listbox mold="select"
+                                                model="@{unitTypes}"
+                                                selectedItem="@{material.unitType}"
+                                                disabled="true" />
+                                        </listcell>
+                                        <listcell label="@{material.defaultUnitPrice}" />
+                                        <listcell label="@{material.category.name}" />
+                                    </listitem>
+                                </listbox>
+                            </panelchildren>
+                        </panel>
+                    </vbox>
+
+                </hbox>
+            </tabpanel>
+        </tabpanels>
+    </tabbox>
+
+</vbox>
diff --git a/navalplanner-webapp/src/main/webapp/orders/_splitMaterialAssignmentDlg.zul b/navalplanner-webapp/src/main/webapp/orders/_splitMaterialAssignmentDlg.zul
new file mode 100644
index 000000000..6b67734af
--- /dev/null
+++ b/navalplanner-webapp/src/main/webapp/orders/_splitMaterialAssignmentDlg.zul
@@ -0,0 +1,29 @@
+<window title="${arg.title}" border="normal" width="250pt" closable="true"
+    use="org.zkoss.zul.impl.MessageboxDlg">
+        <hbox>
+            <div class="${arg.icon}"/>
+            <div sclass="z-messagebox" width="210pt">
+                    <label value="${arg.message}" multiline="true"/>
+            </div>
+        </hbox>
+        <separator spacing="20px"/>
+        <grid>
+            <columns>
+                <column />
+                <column />
+            </columns>
+            <rows>
+                <row>
+                    <label style="font-weight: bold" value="${i18n:_('Units')}:" width="150px" />
+                    <doublebox id="dbUnits" width="200px" />
+                </row>
+            </rows>
+        </grid>
+        <separator bar="true"/>
+        <hbox style="margin-left:auto; margin-right:auto">
+            <button id="btnOk" identity="${arg.OK}" sclass="z-messagebox-btn"
+                use="org.zkoss.zul.impl.MessageboxDlg$Button" />
+            <button id="btnCancel" identity="${arg.CANCEL}" sclass="z-messagebox-btn"
+                use="org.zkoss.zul.impl.MessageboxDlg$Button" />
+        </hbox>
+</window>
diff --git a/navalplanner-webapp/src/test/resources/navalplanner-webapp-spring-config-test.xml b/navalplanner-webapp/src/test/resources/navalplanner-webapp-spring-config-test.xml
index 447e88c7a..ba3f7f973 100644
--- a/navalplanner-webapp/src/test/resources/navalplanner-webapp-spring-config-test.xml
+++ b/navalplanner-webapp/src/test/resources/navalplanner-webapp-spring-config-test.xml
@@ -60,6 +60,9 @@
                 <value>
                     org/navalplanner/business/common/entities/Configuration.hbm.xml
                 </value>
+                <value>
+                    org/navalplanner/business/materials/entities/Materials.hbm.xml
+                </value>
             </list>
         </property>