diff --git a/cipherscan b/cipherscan
index 6efb49c..de17313 100755
--- a/cipherscan
+++ b/cipherscan
@@ -596,6 +596,12 @@ test_serverside_ordering() {
     fi
 }
 
+# If no options are given, give usage information and exit (with error code)
+if [ $# -eq 0 ]; then
+   usage;
+   exit 1
+fi
+
 # UNKNOWNOPTIONS=""
 while :
 do