diff --git a/api/src/main/java/org/openmrs/Cohort.java b/api/src/main/java/org/openmrs/Cohort.java
index c102c05c08a7..41b7d31d7000 100644
--- a/api/src/main/java/org/openmrs/Cohort.java
+++ b/api/src/main/java/org/openmrs/Cohort.java
@@ -338,8 +338,11 @@ public Set<Integer> getMemberIds() {
 	@Deprecated
 	public void setMemberIds(Set<Integer> memberIds) {
 		if (getMemberships().size() == 0) {
+		    Date startDate = new Date();
 			for (Integer id : memberIds) {
-				addMembership(new CohortMembership(id));
+			    CohortMembership membership = new CohortMembership(id, startDate);
+                membership.setCohort(this);
+                getMemberships().add(membership);
 			}
 		}
 		else {
diff --git a/api/src/test/java/org/openmrs/CohortTest.java b/api/src/test/java/org/openmrs/CohortTest.java
index 10361d0c7b95..48e295ed19be 100644
--- a/api/src/test/java/org/openmrs/CohortTest.java
+++ b/api/src/test/java/org/openmrs/CohortTest.java
@@ -9,17 +9,20 @@
  */
 package org.openmrs;
 
-import static org.junit.Assert.assertTrue;
+import org.apache.commons.lang3.StringUtils;
+import org.junit.Assert;
+import org.junit.Test;
 
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Date;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
-import org.apache.commons.lang3.StringUtils;
-import org.junit.Test;
+import static org.junit.Assert.assertTrue;
 
 /**
  * Behavior-driven tests of the Cohort class.
@@ -147,4 +150,19 @@ public void intersect_shouldContainVoidedAndExpiredMemberships() throws Exceptio
 			assertTrue(m.getVoided() && m.getEndDate() != null);
 		});
 	}
+
+    @Test
+    public void setMemberIds_shouldSupportLargeCohorts() {
+	    int cohortSize = 100000;
+        Cohort c = new Cohort();
+        Set<Integer> ids = new HashSet<Integer>();
+        for (int i=0; i<cohortSize; i++) {
+            ids.add(i);
+        }
+        long startTime = System.currentTimeMillis();
+        c.setMemberIds(ids);
+        long endTime = System.currentTimeMillis();
+        double secondsToSet = (endTime - startTime)/1000;
+        Assert.assertTrue("Setting cohort of size " + cohortSize + " took " + secondsToSet + " seconds", secondsToSet < 5);
+    }
 }