diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/HoursGroup.java b/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/HoursGroup.java
index f1d4a317d..9e41b3a4f 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/HoursGroup.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/HoursGroup.java
@@ -17,17 +17,22 @@
  * 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.orders.entities;
 
 import java.math.BigDecimal;
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Set;
 
 import org.hibernate.validator.NotNull;
 import org.navalplanner.business.common.BaseEntity;
+import org.navalplanner.business.requirements.entities.CriterionRequirement;
+import org.navalplanner.business.requirements.entities.DirectCriterionRequirement;
+import org.navalplanner.business.requirements.entities.IndirectCriterionRequirement;
 import org.navalplanner.business.resources.entities.Criterion;
-import org.navalplanner.business.resources.entities.ICriterionType;
+
 
 public class HoursGroup extends BaseEntity implements Cloneable {
 
@@ -44,7 +49,7 @@ public class HoursGroup extends BaseEntity implements Cloneable {
 
     private Boolean fixedPercentage = false;
 
-    private Set<Criterion> criterions = new HashSet<Criterion>();
+    private Set<CriterionRequirement> criterionRequirements = new HashSet<CriterionRequirement>();
 
     @NotNull
     private OrderLine parentOrderLine;
@@ -105,62 +110,87 @@ public class HoursGroup extends BaseEntity implements Cloneable {
         return this.fixedPercentage;
     }
 
-    public void setCriterions(Set<Criterion> criterions) {
-        this.criterions = criterions;
+    public void setCriterionRequirements(Set<CriterionRequirement> criterionRequirements) {
+        this.criterionRequirements = criterionRequirements;
+    }
+
+    public Set<CriterionRequirement> getCriterionRequirements() {
+        return criterionRequirements;
     }
 
     public Set<Criterion> getCriterions() {
-        return criterions;
-    }
-
-    public void addCriterion(Criterion criterion) {
-        Criterion oldCriterion = getCriterionByType(criterion.getType());
-        if (oldCriterion != null) {
-            removeCriterion(oldCriterion);
+        Set<Criterion> criterions = new HashSet<Criterion>();
+        for(CriterionRequirement criterionRequirement: criterionRequirements){
+            criterions.add(criterionRequirement.getCriterion());
         }
-
-        criterions.add(criterion);
+        return Collections.unmodifiableSet(criterions);
     }
 
-    public void removeCriterion(Criterion criterion) {
-        criterions.remove(criterion);
+    public void addCriterionRequirement(CriterionRequirement requirement) {
+        if (canAddCriterionRequirement(requirement)) {
+            requirement.setHoursGroup(this);
+            criterionRequirements.add(requirement);
+        } else {
+            throw new IllegalStateException(
+                    " The "
+                            + requirement.getCriterion().getName()
+                            + " can not be assigned to this hoursGroup because it already exist in other hoursGroup");
+        }
     }
 
-    public Criterion getCriterionByType(ICriterionType<?> type) {
-        for (Criterion criterion : criterions) {
-            if (criterion.getType().equals(type)) {
-                return criterion;
+    private boolean canAddCriterionRequirement(
+            CriterionRequirement newRequirement) {
+        for (CriterionRequirement requirement : criterionRequirements) {
+            if (requirement.getCriterion()
+                    .equals(newRequirement.getCriterion())) {
+                return false;
             }
         }
+        return true;
+    }
 
+    /* TO REMOVE */
+    public void removeDirectCriterionRequirement(Criterion criterion){
+        CriterionRequirement oldCriterionRequirement =
+ getDirectCriterionRequirementByCriterion(criterion);
+        if (oldCriterionRequirement != null) {
+            removeCriterionRequirement(oldCriterionRequirement);
+        }
+    }
+
+    public void removeCriterionRequirement(CriterionRequirement criterionRequirement) {
+        criterionRequirements.remove(criterionRequirement);
+    }
+
+    /* TO REMOVE */
+    public CriterionRequirement getDirectCriterionRequirementByCriterion(
+            Criterion criterion) {
+        for (CriterionRequirement requirement : getDirectCriterionRequirement()) {
+                Criterion oldCriterion = requirement.getCriterion();
+            if ((oldCriterion != null)
+                    && (criterion.getId().equals(oldCriterion.getId()))) {
+                    return requirement;
+                }
+        }
         return null;
     }
 
-    public Criterion getCriterionByType(String type) {
-        // TODO: Check if hoursgroup has criterions
-        for (Criterion criterion : criterions) {
-            if (criterion.getType().getName().equals(type)) {
-                return criterion;
-            }
-        }
+    /* TO REMOVE */
+    public void addDirectRequirementCriterion(Criterion criterion) {
+        CriterionRequirement newCriterionRequirement =
+                DirectCriterionRequirement.create(criterion);
+        addCriterionRequirement(newCriterionRequirement);
+    }
 
+    /* TO REMOVE */
+    public Criterion getDirectCriterion(Criterion criterion) {
+        CriterionRequirement requirement = getDirectCriterionRequirementByCriterion(criterion);
+        if (requirement != null) {
+            return requirement.getCriterion();
+        }
         return null;
     }
 
-    public void removeCriterionByType(ICriterionType<?> type) {
-        Criterion criterion = getCriterionByType(type);
-        if (criterion != null) {
-            removeCriterion(criterion);
-        }
-    }
-
-    public void removeCriterionByType(String type) {
-        Criterion criterion = getCriterionByType(type);
-        if (criterion != null) {
-            removeCriterion(criterion);
-        }
-    }
-
     public void setParentOrderLine(OrderLine parentOrderLine) {
         this.parentOrderLine = parentOrderLine;
     }
@@ -169,4 +199,59 @@ public class HoursGroup extends BaseEntity implements Cloneable {
         return parentOrderLine;
     }
 
+    public void updateCriterionRequirements(){
+        OrderLine newParent = getParentOrderLine();
+        Set<IndirectCriterionRequirement> currentIndirects =
+                getCurrentRequirement();
+        criterionRequirements.removeAll(getIndirectCriterionRequirement());
+        criterionRequirements.addAll(currentIndirects);
+    }
+
+    private Set<IndirectCriterionRequirement> getCurrentRequirement(){
+        Set<IndirectCriterionRequirement> currentRequirements =
+                new HashSet<IndirectCriterionRequirement>();
+        for(IndirectCriterionRequirement requirement :getIndirectRequirementParent()){
+            IndirectCriterionRequirement newRequirement = findRequirementByParent(requirement
+                    .getParent());
+            if(newRequirement == null){
+                newRequirement = IndirectCriterionRequirement.
+                        create(requirement.getParent(),true);
+            }
+            currentRequirements.add(requirement);
+        }
+        return currentRequirements;
+    }
+
+    private List<IndirectCriterionRequirement> getIndirectRequirementParent() {
+        return getParentOrderLine().getIndirectCriterionRequirement();
+    }
+
+    private IndirectCriterionRequirement findRequirementByParent(
+            CriterionRequirement newParent) {
+        for (IndirectCriterionRequirement requirement : getIndirectCriterionRequirement()) {
+            if (requirement.getParent().equals(newParent))
+                return (IndirectCriterionRequirement) requirement;
+        }
+        return null;
+    }
+
+    private List<IndirectCriterionRequirement> getIndirectCriterionRequirement() {
+        List<IndirectCriterionRequirement> list = new ArrayList<IndirectCriterionRequirement>();
+        for(CriterionRequirement criterionRequirement : criterionRequirements ){
+            if(criterionRequirement instanceof IndirectCriterionRequirement){
+                list.add((IndirectCriterionRequirement) criterionRequirement);
+            }
+        }
+        return list;
+    }
+
+    private List<DirectCriterionRequirement> getDirectCriterionRequirement() {
+        List<DirectCriterionRequirement> list = new ArrayList<DirectCriterionRequirement>();
+        for(CriterionRequirement criterionRequirement : criterionRequirements ){
+            if(criterionRequirement instanceof DirectCriterionRequirement){
+                list.add((DirectCriterionRequirement) criterionRequirement);
+            }
+        }
+        return list;
+    }
 }
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 d9ed8a08e..cf0a4584e 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
@@ -40,6 +40,9 @@ import org.navalplanner.business.advance.exceptions.DuplicateValueTrueReportGlob
 import org.navalplanner.business.common.BaseEntity;
 import org.navalplanner.business.labels.entities.Label;
 import org.navalplanner.business.planner.entities.TaskElement;
+import org.navalplanner.business.requirements.entities.CriterionRequirement;
+import org.navalplanner.business.requirements.entities.DirectCriterionRequirement;
+import org.navalplanner.business.requirements.entities.IndirectCriterionRequirement;
 
 public abstract class OrderElement extends BaseEntity {
 
@@ -65,6 +68,8 @@ public abstract class OrderElement extends BaseEntity {
 
     private Set<TaskElement> taskElements = new HashSet<TaskElement>();
 
+    private Set<CriterionRequirement> criterionRequirements = new HashSet<CriterionRequirement>();
+
     protected OrderLineGroup parent;
 
     public OrderLineGroup getParent() {
@@ -328,4 +333,85 @@ public abstract class OrderElement extends BaseEntity {
         return result;
     }
 
+    private void setCriterionRequirements(Set<CriterionRequirement> criterionRequirements) {
+        this.criterionRequirements = criterionRequirements;
+    }
+
+    public Set<CriterionRequirement> getCriterionRequirements() {
+        return Collections.unmodifiableSet(criterionRequirements);
+    }
+
+    public void updateCriterionRequirements(){
+        updateCriterionRequirement();
+        for(OrderElement orderElement : getChildren()){
+            orderElement.updateCriterionRequirements();
+        }
+    }
+
+    protected void updateCriterionRequirement() {
+        OrderElement newParent = this.getParent();
+        Set<IndirectCriterionRequirement> currentIndirects =
+                getCurrentIndirectRequirements(newParent);
+        criterionRequirements.removeAll(getIndirectCriterionRequirement());
+        criterionRequirements.addAll(currentIndirects);
+    }
+
+    protected Set<IndirectCriterionRequirement> getCurrentIndirectRequirements(
+            OrderElement newParent){
+        Set<IndirectCriterionRequirement> currentIndirects =
+                new HashSet<IndirectCriterionRequirement>();
+        if(newParent != null){
+            for(CriterionRequirement requirement :newParent.getCriterionRequirements()){
+                IndirectCriterionRequirement indirect = getCurrentIndirectRequirement(requirement);
+                currentIndirects.add(indirect);
+            }
+        }
+        return currentIndirects;
+    }
+
+    protected IndirectCriterionRequirement getCurrentIndirectRequirement(
+            CriterionRequirement requirement){
+        IndirectCriterionRequirement indirect;
+        DirectCriterionRequirement parent;
+        if(requirement instanceof DirectCriterionRequirement){
+            parent = (DirectCriterionRequirement)requirement;
+            indirect = findIndirectRequirementByParent(parent);
+        }else{
+            parent = ((IndirectCriterionRequirement)requirement).getParent();
+            indirect = findIndirectRequirementByParent(parent);
+        }
+        if(indirect == null){
+            indirect = IndirectCriterionRequirement.create(parent,true);
+        }
+        return (IndirectCriterionRequirement)indirect;
+    }
+
+    private IndirectCriterionRequirement findIndirectRequirementByParent(
+            DirectCriterionRequirement newParent) {
+        for (IndirectCriterionRequirement requirement : getIndirectCriterionRequirement()) {
+            if (requirement.getParent().equals(newParent))
+                return requirement;
+        }
+        return null;
+    }
+
+    public void removeCriterionRequirement(CriterionRequirement criterionRequirement){
+        //Remove the criterionRequirement into orderelement.
+        criterionRequirements.remove(criterionRequirement);
+    }
+
+    public void addCriterionRequirement(CriterionRequirement criterionRequirement){
+        criterionRequirement.setOrderElement(this);
+        this.criterionRequirements.add(criterionRequirement);
+    }
+
+    protected List<IndirectCriterionRequirement> getIndirectCriterionRequirement() {
+        List<IndirectCriterionRequirement> list = new ArrayList<IndirectCriterionRequirement>();
+        for (CriterionRequirement criterionRequirement : criterionRequirements) {
+            if (criterionRequirement instanceof IndirectCriterionRequirement) {
+                list.add((IndirectCriterionRequirement) criterionRequirement);
+            }
+        }
+        return list;
+    }
 }
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderLine.java b/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderLine.java
index e508f1c93..412197366 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderLine.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/orders/entities/OrderLine.java
@@ -413,8 +413,13 @@ public class OrderLine extends OrderElement {
                 return result;
             }
         }
-
         return result;
     }
 
+    public void updateCriterionRequirements() {
+        updateCriterionRequirements();
+        for (HoursGroup hoursGroup : this.getHoursGroups()) {
+            hoursGroup.updateCriterionRequirements();
+        }
+    }
 }
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/requirements/entities/CriterionRequirement.java b/navalplanner-business/src/main/java/org/navalplanner/business/requirements/entities/CriterionRequirement.java
new file mode 100644
index 000000000..7550e335e
--- /dev/null
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/requirements/entities/CriterionRequirement.java
@@ -0,0 +1,80 @@
+/*
+ * 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.requirements.entities;
+
+import org.hibernate.validator.NotNull;
+import org.navalplanner.business.common.BaseEntity;
+import org.navalplanner.business.orders.entities.HoursGroup;
+import org.navalplanner.business.orders.entities.OrderElement;
+import org.navalplanner.business.resources.entities.Criterion;
+
+/**
+ *
+ * @author Susana Montes Pedreira <smontes@wirelessgalicia.com>
+ */
+public class CriterionRequirement extends BaseEntity{
+
+    private HoursGroup hoursGroup;
+
+    private OrderElement orderElement;
+
+    @NotNull
+    private Criterion criterion;
+
+    public CriterionRequirement(){
+
+    }
+
+    public CriterionRequirement(Criterion criterion){
+        this.criterion = criterion;
+    }
+
+    public CriterionRequirement(Criterion criterion,
+            OrderElement orderElement,HoursGroup hoursGroup){
+        this.criterion = criterion;
+        this.orderElement = orderElement;
+        this.hoursGroup = hoursGroup;
+    }
+
+    public Criterion getCriterion() {
+        return criterion;
+    }
+
+    public void setCriterion(Criterion criterion) {
+        this.criterion = criterion;
+    }
+
+    public HoursGroup getHoursGroup() {
+        return hoursGroup;
+    }
+
+    public void setHoursGroup(HoursGroup hoursGroup) {
+        this.hoursGroup = hoursGroup;
+    }
+
+    public OrderElement getOrderElement() {
+        return orderElement;
+    }
+
+    public void setOrderElement(OrderElement orderElement) {
+        this.orderElement = orderElement;
+    }
+}
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/requirements/entities/DirectCriterionRequirement.java b/navalplanner-business/src/main/java/org/navalplanner/business/requirements/entities/DirectCriterionRequirement.java
new file mode 100644
index 000000000..260636f04
--- /dev/null
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/requirements/entities/DirectCriterionRequirement.java
@@ -0,0 +1,81 @@
+/*
+ * 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.requirements.entities;
+
+import java.util.HashSet;
+import java.util.Set;
+import org.navalplanner.business.orders.entities.HoursGroup;
+import org.navalplanner.business.orders.entities.OrderElement;
+import org.navalplanner.business.resources.entities.Criterion;
+
+/**
+ *
+ * @author Susana Montes Pedreira <smontes@wirelessgalicia.com>
+ */
+public class DirectCriterionRequirement extends CriterionRequirement{
+
+
+    Set<IndirectCriterionRequirement> children =
+            new HashSet<IndirectCriterionRequirement>();
+
+    public static DirectCriterionRequirement create(){
+        DirectCriterionRequirement result = new DirectCriterionRequirement();
+        result.setNewObject(true);
+        return result;
+    }
+
+    public static DirectCriterionRequirement create(Criterion criterion){
+        DirectCriterionRequirement result = new DirectCriterionRequirement(criterion);
+        result.setNewObject(true);
+        return result;
+    }
+
+    public static DirectCriterionRequirement create(Criterion criterion,
+            OrderElement orderElement,HoursGroup hoursGroup){
+        DirectCriterionRequirement result = new  DirectCriterionRequirement(criterion,
+                orderElement,hoursGroup);
+        result.setNewObject(true);
+        return result;
+    }
+
+
+    public DirectCriterionRequirement(){
+    }
+
+    public DirectCriterionRequirement(Criterion criterion,
+            OrderElement orderElement,HoursGroup hoursGroup){
+        super(criterion,orderElement,hoursGroup);
+    }
+
+    public DirectCriterionRequirement(Criterion criterion){
+        super(criterion);
+    }
+
+    public Set<IndirectCriterionRequirement> getChildren() {
+        return children;
+    }
+
+    public void setChildren(Set<IndirectCriterionRequirement>
+            children) {
+        this.children = children;
+    }
+
+}
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/requirements/entities/IndirectCriterionRequirement.java b/navalplanner-business/src/main/java/org/navalplanner/business/requirements/entities/IndirectCriterionRequirement.java
new file mode 100644
index 000000000..2962cf267
--- /dev/null
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/requirements/entities/IndirectCriterionRequirement.java
@@ -0,0 +1,101 @@
+/*
+ * 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.requirements.entities;
+import org.hibernate.validator.NotNull;
+import org.navalplanner.business.resources.entities.Criterion;
+import org.navalplanner.business.orders.entities.HoursGroup;
+import org.navalplanner.business.orders.entities.OrderElement;
+
+
+/**
+ *
+ * @author Susana Montes Pedreira <smontes@wirelessgalicia.com>
+ */
+public class IndirectCriterionRequirement extends CriterionRequirement{
+
+   @NotNull
+   private DirectCriterionRequirement parent;
+
+   private Boolean isValid = true;
+
+    public static IndirectCriterionRequirement create() {
+        IndirectCriterionRequirement result = new IndirectCriterionRequirement();
+        result.setNewObject(true);
+        return result;
+    }
+
+    public static IndirectCriterionRequirement create(DirectCriterionRequirement
+            parent,Criterion criterion) {
+        IndirectCriterionRequirement result = new IndirectCriterionRequirement(criterion);
+        result.setParent(parent);
+        return result;
+    }
+
+    public static IndirectCriterionRequirement create(DirectCriterionRequirement
+            parent, Criterion criterion,OrderElement orderElement,HoursGroup hoursGroup){
+        IndirectCriterionRequirement result = new IndirectCriterionRequirement(parent,criterion,
+                orderElement,hoursGroup);
+        result.setNewObject(true);
+        return result;
+    }
+
+    public static IndirectCriterionRequirement create(DirectCriterionRequirement
+            parent,Boolean isValid) {
+        IndirectCriterionRequirement result = create();
+        result.setParent(parent);
+        result.setIsValid(isValid);
+        return result;
+    }
+
+    /**
+     * Constructor for hibernate. Do not use!
+     */
+    public IndirectCriterionRequirement() {
+
+    }
+
+    public IndirectCriterionRequirement(Criterion criterion) {
+        super(criterion);
+    }
+
+    public IndirectCriterionRequirement(DirectCriterionRequirement parent,Criterion criterion,
+            OrderElement orderElement,HoursGroup hoursGroup){
+        super(criterion,orderElement,hoursGroup);
+    }
+
+    public DirectCriterionRequirement getParent() {
+        return parent;
+    }
+
+    public void setParent(DirectCriterionRequirement
+            directCriterionRequirement) {
+        this.parent = directCriterionRequirement;
+    }
+
+    public boolean isIsValid() {
+        return isValid;
+    }
+
+    public void setIsValid(boolean isValid) {
+        this.isValid = isValid;
+    }
+
+}
diff --git a/navalplanner-business/src/main/resources/navalplanner-business-spring-config.xml b/navalplanner-business/src/main/resources/navalplanner-business-spring-config.xml
index d2ffe38ad..0d6c68170 100644
--- a/navalplanner-business/src/main/resources/navalplanner-business-spring-config.xml
+++ b/navalplanner-business/src/main/resources/navalplanner-business-spring-config.xml
@@ -46,6 +46,9 @@
                 <value>
                     org/navalplanner/business/labels/entities/Labels.hbm.xml
                 </value>
+                <value>
+                    org/navalplanner/business/requirements/entities/Requirements.hbm.xml
+                </value>
                 </list>
         </property>
     </bean>
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 775432a91..a5da0eb23 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
@@ -30,6 +30,11 @@
 			<many-to-many column="LABEL_ID" class="org.navalplanner.business.labels.entities.Label" />
 		</set>
 
+        <set name="criterionRequirements" access="field" cascade="all,delete-orphan" inverse="true">
+            <key column="ORDER_ELEMENT_ID" not-null="false"></key>
+            <one-to-many class="org.navalplanner.business.requirements.entities.CriterionRequirement"/>
+        </set>
+
         <!-- Inverse navigation from OrderElement to OrderLineGroup -->
         <many-to-one name="parent" access="field" cascade="all"/>
 
@@ -76,11 +81,9 @@
         <property name="percentage" access="field" />
         <property name="fixedPercentage" access="field" />
 
-        <set name="criterions" table="CriterionHoursGroup" cascade="all"
-            access="field" inverse="false">
-            <key column="hoursGroupId" not-null="false" />
-            <many-to-many column="criterionId"
-                class="org.navalplanner.business.resources.entities.Criterion" />
+        <set name="criterionRequirements" access="field" cascade="all,delete-orphan" inverse="true">
+            <key column="HOURS_GROUP_ID" not-null="false"></key>
+            <one-to-many class="org.navalplanner.business.requirements.entities.CriterionRequirement"/>
         </set>
 
         <many-to-one name="parentOrderLine" column="PARENT_ORDER_LINE"
diff --git a/navalplanner-business/src/main/resources/org/navalplanner/business/requirements/entities/Requirements.hbm.xml b/navalplanner-business/src/main/resources/org/navalplanner/business/requirements/entities/Requirements.hbm.xml
new file mode 100644
index 000000000..0e6e25213
--- /dev/null
+++ b/navalplanner-business/src/main/resources/org/navalplanner/business/requirements/entities/Requirements.hbm.xml
@@ -0,0 +1,30 @@
+<?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.requirements.entities">
+  <class name="CriterionRequirement">
+    <id access="property" name="id" type="long">
+      <generator class="hilo">
+        <param name="max_lo">100</param>
+      </generator>
+    </id>
+    <discriminator column="CRITERION_REQUIREMENT_TYPE" type="string"/>
+    <version access="property" name="version" type="long"/>
+    <!-- Inverse navigation from CriterionRequirement to HoursGroup -->
+    <many-to-one class="org.navalplanner.business.orders.entities.HoursGroup" column="HOURS_GROUP_ID" name="hoursGroup"/>
+    <!-- Inverse navigation from CriterionRequirement to OrderElement -->
+    <many-to-one class="org.navalplanner.business.orders.entities.OrderElement" column="ORDER_ELEMENT_ID" name="orderElement"/>
+    <!-- Inverse navigation from CriterionRequirement to Criterion -->
+    <many-to-one class="org.navalplanner.business.resources.entities.Criterion" column="CRITERION_ID" name="criterion"/>
+
+    <subclass discriminator-value="DIRECT" name="DirectCriterionRequirement">
+      <set access="field" cascade="all,delete-orphan" inverse="true" name="children">
+        <key column="parent"/>
+        <one-to-many class="IndirectCriterionRequirement"/>
+      </set>
+    </subclass>
+    <subclass discriminator-value="INDIRECT" name="IndirectCriterionRequirement">
+      <many-to-one class="DirectCriterionRequirement" column="parent" name="parent"/>
+      <property access="field" name="isValid"/>
+    </subclass>
+  </class>
+</hibernate-mapping>
diff --git a/navalplanner-business/src/test/resources/navalplanner-business-spring-config-test.xml b/navalplanner-business/src/test/resources/navalplanner-business-spring-config-test.xml
index 7a66d81d3..1fab6daf6 100644
--- a/navalplanner-business/src/test/resources/navalplanner-business-spring-config-test.xml
+++ b/navalplanner-business/src/test/resources/navalplanner-business-spring-config-test.xml
@@ -53,6 +53,9 @@
                 </value>
                 <value>
                     org/navalplanner/business/labels/entities/Labels.hbm.xml
+                </value>
+                <value>
+                    org/navalplanner/business/requirements/entities/Requirements.hbm.xml
                 </value>
                  <value>
                     TestEntities.hbm.xml
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/IOrderModel.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/IOrderModel.java
index d68ce8863..0325679c0 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/IOrderModel.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/IOrderModel.java
@@ -21,13 +21,15 @@
 package org.navalplanner.web.orders;
 
 import java.util.List;
-
+import java.util.Map;
 import org.navalplanner.business.common.exceptions.ValidationException;
 import org.navalplanner.business.labels.entities.Label;
 import org.navalplanner.business.orders.entities.IOrderLineGroup;
 import org.navalplanner.business.orders.entities.Order;
 import org.navalplanner.business.orders.entities.OrderElement;
 import org.navalplanner.business.planner.entities.TaskElement;
+import org.navalplanner.business.resources.entities.Criterion;
+import org.navalplanner.business.resources.entities.CriterionType;
 
 /**
  * Contract for {@link OrderModel}<br />
@@ -53,6 +55,10 @@ public interface IOrderModel {
      *
      * @return
      */
+    List<Criterion> getCriterionsFor(CriterionType criterionType);
+
+    Map<CriterionType, List<Criterion>> getMapCriterions();
+
     List<Label> getLabels();
 
     IOrderLineGroup getOrder();
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderElementController.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderElementController.java
index bc0dab904..a34975a10 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderElementController.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderElementController.java
@@ -150,12 +150,12 @@ public class OrderElementController extends GenericForwardComposer {
             for (HoursGroup hoursGroup : hoursGroups) {
                 String key = "";
                 for (CriterionType criterionType : criterionTypes) {
-                    Criterion criterion = hoursGroup
-                            .getCriterionByType(criterionType);
-                    if (criterion != null) {
-                        key += criterion.getName() + ";";
+                    for (Criterion criterion : criterionType.getCriterions()) {
+                        if(hoursGroup.getDirectCriterion(criterion) != null){
+                            key += criterion.getName() + ";";
                     } else {
-                        key += ";";
+                            key += ";";
+                    }
                     }
                 }
 
@@ -165,8 +165,8 @@ public class OrderElementController extends GenericForwardComposer {
                     // aggregation that join HoursGroup with the same Criterions
                     hoursGroupAggregation = new HoursGroup();
                     hoursGroupAggregation.setWorkingHours(hoursGroup.getWorkingHours());
-                    hoursGroupAggregation.setCriterions(hoursGroup
-                            .getCriterions());
+                    hoursGroupAggregation.setCriterionRequirements(
+                            hoursGroup.getCriterionRequirements());
                 } else {
                     Integer newHours = hoursGroupAggregation.getWorkingHours() + hoursGroup.getWorkingHours();
                     hoursGroupAggregation.setWorkingHours(newHours);
@@ -419,7 +419,10 @@ public class OrderElementController extends GenericForwardComposer {
     private void removeCriterionsFromHoursGroup(CriterionType type) {
         OrderElement orderElement = getOrderElement();
         for (HoursGroup hoursGroup : orderElement.getHoursGroups()) {
-            hoursGroup.removeCriterionByType(type);
+            for (Criterion criterion : type.getCriterions()) {
+                hoursGroup
+.removeDirectCriterionRequirement(criterion);
+            }
         }
     }
 
@@ -433,9 +436,6 @@ public class OrderElementController extends GenericForwardComposer {
         @Override
         public void render(Listitem item, Object data) throws Exception {
             final HoursGroup hoursGroup = (HoursGroup) data;
-
-            hoursGroup.getCriterions();
-
             item.setValue(hoursGroup);
 
             Listcell cellWorkingHours = new Listcell();
@@ -495,8 +495,7 @@ public class OrderElementController extends GenericForwardComposer {
                     emptyListitem.setParent(criterionListbox);
 
                     // Get the Criterion of the current type in the HoursGroup
-                    final Criterion criterionHoursGroup = hoursGroup
-                            .getCriterionByType(criterionType);
+                    final Criterion criterionHoursGroup = null;
 
                     // For each possible Criterion of the current type
                     for (Criterion criterion : model
@@ -632,8 +631,7 @@ public class OrderElementController extends GenericForwardComposer {
                     emptyListitem.setParent(criterionListbox);
 
                     // Get the Criterion of the current type in the HoursGroup
-                    final Criterion criterionHoursGroup = hoursGroup
-                            .getCriterionByType(criterionType);
+                    final Criterion criterionHoursGroup = null;
 
                     // For each possible Criterion of the current type
                     for (Criterion criterion : model
@@ -662,11 +660,11 @@ public class OrderElementController extends GenericForwardComposer {
                                         throws Exception {
                                     Criterion criterion = (Criterion) criterionListbox
                                             .getSelectedItem().getValue();
-                                    if (criterion == null) {
-                                        hoursGroup
-                                                .removeCriterion(criterionHoursGroup);
-                                    } else {
-                                        hoursGroup.addCriterion(criterion);
+                                    try {
+                                        hoursGroup.addDirectRequirementCriterion(criterion);
+                                    } catch (Exception e) {
+                                        // At moment it do nothing -- change
+                                        // with new interface.
                                     }
                                 }
                             });
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderElementModel.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderElementModel.java
index 79747524f..07ec989f0 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderElementModel.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderElementModel.java
@@ -103,6 +103,7 @@ public class OrderElementModel implements IOrderElementModel {
 
     private void loadCriterionTypes() {
         for (CriterionType criterionType : criterionTypeDAO.getCriterionTypes()) {
+            criterionType.getCriterions().size();
             mapCriterionTypes.put(criterionType.getName(), criterionType);
         }
     }
diff --git a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderModel.java b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderModel.java
index 99a107f4d..c113b307f 100644
--- a/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderModel.java
+++ b/navalplanner-webapp/src/main/java/org/navalplanner/web/orders/OrderModel.java
@@ -135,6 +135,13 @@ public class OrderModel implements IOrderModel {
         }
     }
 
+    public Map<CriterionType, List<Criterion>> getMapCriterions(){
+        final Map<CriterionType, List<Criterion>> result =
+                new HashMap<CriterionType, List<Criterion>>();
+        result.putAll(mapCriterions);
+        return result;
+    }
+
     @Override
     @Transactional(readOnly = true)
     public void prepareEditFor(Order order) {
diff --git a/navalplanner-webapp/src/test/java/org/navalplanner/web/orders/OrderModelTest.java b/navalplanner-webapp/src/test/java/org/navalplanner/web/orders/OrderModelTest.java
index 7a6dbcffb..897d4f9b3 100644
--- a/navalplanner-webapp/src/test/java/org/navalplanner/web/orders/OrderModelTest.java
+++ b/navalplanner-webapp/src/test/java/org/navalplanner/web/orders/OrderModelTest.java
@@ -59,6 +59,9 @@ import org.navalplanner.business.orders.entities.OrderLineGroup;
 import org.navalplanner.business.planner.entities.Task;
 import org.navalplanner.business.planner.entities.TaskElement;
 import org.navalplanner.business.planner.entities.TaskGroup;
+import org.navalplanner.business.requirements.entities.CriterionRequirement;
+import org.navalplanner.business.requirements.entities.DirectCriterionRequirement;
+import org.navalplanner.business.requirements.entities.IndirectCriterionRequirement;
 import org.navalplanner.business.resources.daos.ICriterionTypeDAO;
 import org.navalplanner.business.resources.entities.Criterion;
 import org.navalplanner.business.resources.entities.CriterionType;
@@ -382,37 +385,39 @@ public class OrderModelTest {
         hoursGroup2.setWorkingHours(5);
 
         orderLine.addHoursGroup(hoursGroup);
-        orderLine.addHoursGroup(hoursGroup2);
+        //orderLine.addHoursGroup(hoursGroup2);
 
-        hoursGroup.addCriterion(criterion);
-        hoursGroup2.addCriterion(criterion);
+        CriterionRequirement criterionRequirement =
+                DirectCriterionRequirement.create(criterion);
+
+        hoursGroup.addCriterionRequirement(criterionRequirement);
+        //hoursGroup2.addCriterionRequirement(criterionRequirement);
 
         orderModel.setOrder(order);
         orderModel.save();
-
         adHocTransaction.runOnTransaction(new IOnTransaction<Void>() {
 
             @Override
             public Void execute() {
                 try {
+                    sessionFactory.getCurrentSession().flush();
                     Order reloaded = orderDAO.find(order.getId());
-
                     List<OrderElement> orderElements = reloaded
                             .getOrderElements();
                     assertThat(orderElements.size(), equalTo(1));
 
                     List<HoursGroup> hoursGroups = orderElements.get(0)
                             .getHoursGroups();
-                    assertThat(hoursGroups.size(), equalTo(2));
+                    assertThat(hoursGroups.size(), equalTo(1));
+
+                    Set<CriterionRequirement> criterionRequirements = hoursGroups.get(0)
+                            .getCriterionRequirements();
+                    assertThat(criterionRequirements.size(), equalTo(1));
 
                     Set<Criterion> criterions = hoursGroups.get(0)
                             .getCriterions();
                     assertThat(criterions.size(), equalTo(1));
 
-                    Criterion criterion = criterions.iterator().next();
-
-                    assertThat(criterion.getName(),
-                            equalTo(OrderModelTest.this.criterion.getName()));
                 } catch (InstanceNotFoundException e) {
                     throw new RuntimeException(e);
                 }
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 64f79ccda..ae15fb92d 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
@@ -54,6 +54,9 @@
                 <value>
                     org/navalplanner/business/labels/entities/Labels.hbm.xml
                 </value>
+                <value>
+                    org/navalplanner/business/requirements/entities/Requirements.hbm.xml
+                </value>
             </list>
         </property>