diff --git a/qubes-rpc/qvm-run b/qubes-rpc/qvm-run
index 5bc50e3..f4aa2da 100755
--- a/qubes-rpc/qvm-run
+++ b/qubes-rpc/qvm-run
@@ -45,5 +45,8 @@ shift
 
 if [ "$VMNAME" = "--dispvm" ] ; then
     VMNAME='$dispvm'
+elif [ "$VMNAME" = "" ] ; then
+    print_usage
+    exit 1
 fi
 exec /usr/lib/qubes/qrexec-client-vm "$VMNAME" qubes.VMShell "/usr/lib/qubes/qrun-in-vm" "$@"