diff --git a/app/stackage-update.hs b/app/stackage-update.hs
--- a/app/stackage-update.hs
+++ b/app/stackage-update.hs
@@ -1,6 +1,6 @@
 import Stackage.Update
 import System.Environment (getArgs)
-import Data.List ((++))
+import Data.List ((++), concat, intersperse)
 
 main :: IO ()
 main = do
@@ -9,4 +9,7 @@
         ["--help"] -> putStrLn $ "Usage: stackage-update \n" ++
                       "Run this command with no arguments to update your package index."
         ["--summary"] -> putStrLn "Update your package index incrementally (requires git)"
-        _ -> stackageUpdate defaultStackageUpdateSettings
+        [] -> stackageUpdate defaultStackageUpdateSettings
+        xs -> putStrLn $ "stackage-update: unrecognized argument \'" ++
+              (concat $ intersperse " " xs) ++ "\'\nTry \'stackage-update --help\' for more information"
+
diff --git a/stackage-update.cabal b/stackage-update.cabal
--- a/stackage-update.cabal
+++ b/stackage-update.cabal
@@ -1,5 +1,5 @@
 name:                stackage-update
-version:             0.1.0.1
+version:             0.1.0.2
 synopsis:            Update your package index incrementally (requires git)
 homepage:            https://github.com/fpco/stackage-update
 license:             MIT