diff --git a/amrun.cabal b/amrun.cabal
--- a/amrun.cabal
+++ b/amrun.cabal
@@ -1,5 +1,5 @@
 Name:                amrun
-Version:             0.0.0.6
+Version:             0.0.0.7
 Synopsis:            Interpreter for AM
 Description:         The package contains an interpreter for the AM-Language that is introduced in the basic programming course \"Algorithmisches Denken und imperative Programmierung\" (WS 2011/12 and later) at the University of Bonn.
 License:             GPL
diff --git a/src/amrun.hs b/src/amrun.hs
--- a/src/amrun.hs
+++ b/src/amrun.hs
@@ -17,6 +17,7 @@
              | STORE Int | LIT Int | ADD | MUL
              | SUB | DIV | MOD | LT | EQ | NE
              | GT | LE | GE | JMP Int | JMC Int
+             | NOP
      deriving (Show, Eq)
 
 
@@ -59,6 +60,7 @@
 step (JMC e) (m,0:d',h,inp,out) = (e,d',h,inp,out)
 step (JMC e) (m,1:d',h,inp,out) = (m+1,d',h,inp,out)
 step (JMC _) (m,_:_,_,_,_) = error $ "In Programmzeile " ++ show m ++ ", versuchter JMC, obwohl Datenkellerspitze weder 0 noch 1."
+step NOP (m,d,h,inp,out) = (m+1,d,h,inp,out)
 step _ (m,[],_,_,_) =
    error $ "In Programmzeile " ++ show m ++ ", Versuch auf leeren Datenkeller zuzugreifen."
 step _ (m,[_],_,_,_) =
@@ -74,7 +76,6 @@
                      | a>n  = (n,c):(a,b):h
 update []        n c = [(n,c)]
 
-
 run :: [Command] -> (Int,[Int],[(Int,Int)],[Int],[Int])
        -> [(Int,[Int],[(Int,Int)],[Int],[Int])]
 run prog conf = if valid prog conf then conf:(run prog (next prog conf))
@@ -153,7 +154,7 @@
                    arg <- (pcParser <?> "command argument")
                    if cmd == "LIT"  || cmd == "JMC" || cmd == "JMP"
                      then return (c (sign*arg))
-                     else (if arg == 0 then unexpected (cmd ++ " does not take 0 as argument.") else return (c arg))
+                     else return (c arg)
        Nothing -> unexpected (cmd ++ " is not a command.")
                    }
   where
@@ -170,6 +171,7 @@
                    "GT"  -> Just GT
                    "LE"  -> Just LE
                    "GE"  -> Just GE
+                   "NOP" -> Just NOP
                    _     -> Nothing
     readCmd' cmd = case cmd of
                     "READ"  -> Just READ