diff --git a/src/main/java/org/apache/commons/collections/set/CompositeSet.java b/src/main/java/org/apache/commons/collections/set/CompositeSet.java
index 3163bd318..54650f41b 100644
--- a/src/main/java/org/apache/commons/collections/set/CompositeSet.java
+++ b/src/main/java/org/apache/commons/collections/set/CompositeSet.java
@@ -27,6 +27,7 @@ import java.util.List;
 import java.util.Set;
 
 import org.apache.commons.collections.CollectionUtils;
+import org.apache.commons.collections.collection.CompositeCollection;
 import org.apache.commons.collections.iterators.EmptyIterator;
 import org.apache.commons.collections.iterators.IteratorChain;
 import org.apache.commons.collections.list.UnmodifiableList;