diff --git a/src/PETPVC.cxx b/src/PETPVC.cxx
index 84c7309..8b5556c 100644
--- a/src/PETPVC.cxx
+++ b/src/PETPVC.cxx
@@ -154,7 +154,7 @@ int main(int argc, char *argv[])
     //Parse command line.
     if (!command.Parse(argc, argv)) {
 		printPVCMethodList();
-        return EXIT_FAILURE;
+		return EXIT_SUCCESS;
     }
 
     //Get image filenames