diff --git a/java/src/org/broadinstitute/sting/gatk/traversals/TraversalEngine.java b/java/src/org/broadinstitute/sting/gatk/traversals/TraversalEngine.java
index 4971b2efd..e87f99fd2 100755
--- a/java/src/org/broadinstitute/sting/gatk/traversals/TraversalEngine.java
+++ b/java/src/org/broadinstitute/sting/gatk/traversals/TraversalEngine.java
@@ -179,6 +179,8 @@ public abstract class TraversalEngine {
      * @return the header if it's stored, null if not
      */
     public SAMFileHeader getSAMHeader() {
+        if ( myHeader == null )
+            myHeader = samReader.getFileHeader();
         return myHeader;
     }