diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/resources/entities/ICriterion.java b/navalplanner-business/src/main/java/org/navalplanner/business/resources/entities/ICriterion.java
index c6d953557..663c5f2d1 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/resources/entities/ICriterion.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/resources/entities/ICriterion.java
@@ -3,9 +3,7 @@ package org.navalplanner.business.resources.entities;
 import java.util.Date;
 
 /**
- * Responsible of searching the resources satisfiying some condition or set of
- * conditions. <br />
- * Created at May 12, 2009
+ * It's a predicate that can be applied on resources <br />
  * @author Óscar González Fernández <ogonzalez@igalia.com>
  */
 public interface ICriterion {
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/resources/entities/ICriterionOnData.java b/navalplanner-business/src/main/java/org/navalplanner/business/resources/entities/ICriterionOnData.java
new file mode 100644
index 000000000..78652f1da
--- /dev/null
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/resources/entities/ICriterionOnData.java
@@ -0,0 +1,18 @@
+package org.navalplanner.business.resources.entities;
+
+import java.util.Collection;
+import java.util.Date;
+
+/**
+ * Expands the capabilities of {@link ICriterion}. It also lets retrieve the
+ * resources satisfying the criterion <br />
+ * @author Óscar González Fernández <ogonzalez@igalia.com>
+ */
+public interface ICriterionOnData extends ICriterion {
+
+    Collection<Resource> getResourcesSatisfying();
+
+    Collection<Resource> getResourcesSatisfying(Date start, Date end)
+            throws IllegalArgumentException;
+
+}
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/resources/services/CriterionService.java b/navalplanner-business/src/main/java/org/navalplanner/business/resources/services/CriterionService.java
index 0b33c5dfb..16751ec4f 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/resources/services/CriterionService.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/resources/services/CriterionService.java
@@ -8,6 +8,7 @@ import org.navalplanner.business.common.exceptions.InstanceNotFoundException;
 import org.navalplanner.business.resources.entities.Criterion;
 import org.navalplanner.business.resources.entities.CriterionSatisfaction;
 import org.navalplanner.business.resources.entities.ICriterion;
+import org.navalplanner.business.resources.entities.ICriterionOnData;
 import org.navalplanner.business.resources.entities.ICriterionType;
 import org.navalplanner.business.resources.entities.Resource;
 
@@ -40,4 +41,6 @@ public interface CriterionService {
 
     boolean exists(Criterion criterion);
 
+    ICriterionOnData empower(ICriterion criterion);
+
 }
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/resources/services/impl/CriterionServiceImpl.java b/navalplanner-business/src/main/java/org/navalplanner/business/resources/services/impl/CriterionServiceImpl.java
index cec2a72d6..8e8c8ae2d 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/resources/services/impl/CriterionServiceImpl.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/resources/services/impl/CriterionServiceImpl.java
@@ -12,11 +12,13 @@ import org.navalplanner.business.resources.daos.impl.CriterionSatisfactionDAO;
 import org.navalplanner.business.resources.entities.Criterion;
 import org.navalplanner.business.resources.entities.CriterionSatisfaction;
 import org.navalplanner.business.resources.entities.ICriterion;
+import org.navalplanner.business.resources.entities.ICriterionOnData;
 import org.navalplanner.business.resources.entities.ICriterionType;
 import org.navalplanner.business.resources.entities.Resource;
 import org.navalplanner.business.resources.services.CriterionService;
 import org.navalplanner.business.resources.services.ResourceService;
 import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ApplicationContext;
 import org.springframework.transaction.annotation.Transactional;
 
 /**
@@ -112,4 +114,43 @@ public class CriterionServiceImpl implements CriterionService {
         if (!exists(criterion))
             save(criterion);
     }
+
+    @Override
+    public ICriterionOnData empower(final ICriterion criterion) {
+        final CriterionService criterionService = getProxifiedCriterionService();
+        return new ICriterionOnData() {
+            @Override
+            public boolean isSatisfiedBy(Resource resource) {
+                return criterion.isSatisfiedBy(resource);
+            }
+
+            @Override
+            public boolean isSatisfiedBy(Resource resource, Date start, Date end) {
+                return criterion.isSatisfiedBy(resource, start, end);
+            }
+
+            @Override
+            public Collection<Resource> getResourcesSatisfying() {
+                return criterionService.getResourcesSatisfying(criterion);
+            }
+
+            @Override
+            public Collection<Resource> getResourcesSatisfying(Date start,
+                    Date end) throws IllegalArgumentException {
+                return criterionService.getResourcesSatisfying(criterion,
+                        start, end);
+            }
+        };
+    }
+
+    @Autowired
+    private ApplicationContext applicationContext;
+
+    // this is a hack to avoid using the this variable in empower method. The
+    // this instance is not proxified because spring uses an transparent proxy,
+    // so it doesn't open the transacion
+    private CriterionService getProxifiedCriterionService() {
+        return (CriterionService) applicationContext.getBeansOfType(
+                CriterionService.class).values().iterator().next();
+    }
 }
diff --git a/navalplanner-business/src/test/java/org/navalplanner/business/test/resources/services/CriterionServiceTest.java b/navalplanner-business/src/test/java/org/navalplanner/business/test/resources/services/CriterionServiceTest.java
index e33b22932..836d59ca6 100644
--- a/navalplanner-business/src/test/java/org/navalplanner/business/test/resources/services/CriterionServiceTest.java
+++ b/navalplanner-business/src/test/java/org/navalplanner/business/test/resources/services/CriterionServiceTest.java
@@ -13,6 +13,7 @@ import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.navalplanner.business.resources.entities.Criterion;
 import org.navalplanner.business.resources.entities.CriterionSatisfaction;
+import org.navalplanner.business.resources.entities.ICriterionOnData;
 import org.navalplanner.business.resources.entities.ICriterionType;
 import org.navalplanner.business.resources.entities.PredefinedCriterionTypes;
 import org.navalplanner.business.resources.entities.Worker;
@@ -23,6 +24,7 @@ import org.navalplanner.business.test.resources.daos.CriterionSatisfactionDAOTes
 import org.navalplanner.business.test.resources.entities.ResourceTest;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.dao.DataIntegrityViolationException;
+import org.springframework.test.annotation.NotTransactional;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.transaction.annotation.Transactional;
@@ -160,6 +162,44 @@ public class CriterionServiceTest {
                 .size());
     }
 
+    @Test
+    public void shouldLetCreateCriterionOnData() {
+        Criterion criterion = CriterionDAOTest.createValidCriterion();
+        criterionService.save(criterion);
+        Worker worker = new Worker("firstName", "surName", "2333232", 10);
+        resourceService.saveResource(worker);
+        CriterionSatisfaction criterionSatisfaction = new CriterionSatisfaction(
+                CriterionSatisfactionDAOTest.year(2000), criterion, worker);
+        criterionService.add(criterionSatisfaction);
+        ICriterionOnData criterionOnData = criterionService.empower(criterion);
+        assertTrue(criterionOnData.isSatisfiedBy(worker));
+        assertEquals(1, criterionOnData.getResourcesSatisfying().size());
+        assertTrue(criterionOnData.getResourcesSatisfying().contains(worker));
+        assertTrue(criterionOnData.getResourcesSatisfying(
+                CriterionSatisfactionDAOTest.year(1990),
+                CriterionSatisfactionDAOTest.year(2005)).isEmpty());
+        assertEquals(1, criterionOnData.getResourcesSatisfying(
+                CriterionSatisfactionDAOTest.year(2001),
+                CriterionSatisfactionDAOTest.year(2005)).size());
+    }
+
+    @Test
+    @NotTransactional
+    public void shouldntThrowExceptionDueToTransparentProxyGotcha() {
+        Criterion criterion = CriterionDAOTest.createValidCriterion();
+        criterionService.save(criterion);
+        Worker worker = new Worker("firstName", "surName", "2333232", 10);
+        resourceService.saveResource(worker);
+        CriterionSatisfaction criterionSatisfaction = new CriterionSatisfaction(
+                CriterionSatisfactionDAOTest.year(2000), criterion, worker);
+        criterionService.add(criterionSatisfaction);
+        ICriterionOnData criterionOnData = criterionService.empower(criterion);
+        criterionOnData.getResourcesSatisfying();
+        criterionOnData.getResourcesSatisfying(
+                CriterionSatisfactionDAOTest.year(2001),
+                CriterionSatisfactionDAOTest.year(2005));
+    }
+
     @Test(expected = IllegalArgumentException.class)
     public void mustBeCorrectInterval() {
         Criterion criterion = CriterionDAOTest.createValidCriterion();
@@ -225,7 +265,6 @@ public class CriterionServiceTest {
         assertEquals(2, criterionService.getSatisfactionsFor(criterionType,
                 CriterionSatisfactionDAOTest.year(1999),
                 CriterionSatisfactionDAOTest.year(2005)).size());
-
     }
 
 }