diff --git a/src/java/com/samskivert/util/AbstractIntSet.java b/src/java/com/samskivert/util/AbstractIntSet.java
index d8265f2d..2044b731 100644
--- a/src/java/com/samskivert/util/AbstractIntSet.java
+++ b/src/java/com/samskivert/util/AbstractIntSet.java
@@ -71,6 +71,18 @@ public abstract class AbstractIntSet extends AbstractSet<Integer>
         return size;
     }
 
+    /**
+     * {@inheritDoc}
+     *
+     * <p>This implementation simply checks to see if the interator has a first element.
+     */
+    @Override
+    public boolean isEmpty ()
+    {
+        // possibly dumb implementation. Override if you can do better.
+        return !interator().hasNext();
+    }
+
     // from IntSet
     public boolean add (int value)
     {
diff --git a/src/java/com/samskivert/util/ArrayIntSet.java b/src/java/com/samskivert/util/ArrayIntSet.java
index 3dc03304..27f3097b 100644
--- a/src/java/com/samskivert/util/ArrayIntSet.java
+++ b/src/java/com/samskivert/util/ArrayIntSet.java
@@ -268,12 +268,18 @@ public class ArrayIntSet extends AbstractIntSet
         return values;
     }
 
-    @Override // from AbstractSet<Integer>
+    @Override // from AbstractCollection<Integer>
     public int size ()
     {
         return _size;
     }
 
+    @Override // from AbstractCollection<Integer>
+    public boolean isEmpty ()
+    {
+        return (_size == 0);
+    }
+
     @Override // from AbstractIntSet
     public boolean retainAll (Collection<?> c)
     {
diff --git a/src/java/com/samskivert/util/IntSets.java b/src/java/com/samskivert/util/IntSets.java
index a2a197b3..e1027b0a 100644
--- a/src/java/com/samskivert/util/IntSets.java
+++ b/src/java/com/samskivert/util/IntSets.java
@@ -210,6 +210,7 @@ public class IntSets
     {
         @Override public boolean contains (int value) { return false; }
         @Override public int size () { return 0; }
+        @Override public boolean isEmpty () { return true; }
 
         public Interator interator ()
         {
@@ -233,8 +234,9 @@ public class IntSets
             _s = s;
         }
 
-        @Override public int size () { return _s.size(); }
         @Override public boolean contains (int value) { return _s.contains(value); }
+        @Override public int size () { return _s.size(); }
+        @Override public boolean isEmpty () { return _s.isEmpty(); }
 
         public Interator interator ()
         {