diff --git a/data-accessor-template.cabal b/data-accessor-template.cabal
--- a/data-accessor-template.cabal
+++ b/data-accessor-template.cabal
@@ -1,5 +1,5 @@
 Name:             data-accessor-template
-Version:          0.1.2
+Version:          0.1.3
 License:          GPL
 License-File:     LICENSE
 Author:           Henning Thielemann <haskell@henning-thielemann.de>, Luke Palmer <lrpalmer@gmail.com>
diff --git a/src/Data/Accessor/Template.hs b/src/Data/Accessor/Template.hs
--- a/src/Data/Accessor/Template.hs
+++ b/src/Data/Accessor/Template.hs
@@ -15,7 +15,7 @@
   -- (Q, Exp(VarE), Pat(VarP), Dec(ValD), Name(Name), mkOccName, occString, reify, )
 
 import Data.Maybe (catMaybes)
-import Control.Monad (guard, liftM, )
+import Control.Monad (guard, liftM, when)
 
 
 
@@ -27,7 +27,7 @@
 -- It is "nameDeriveAccessors" n f where @f@ satisfies
 --
 -- > f (s ++ "_") = Just s
--- > f x          = x       -- otherwise
+-- > f x          = Nothing    -- otherwise
 --
 -- For example, given the data type:
 --
@@ -43,6 +43,12 @@
 -- > p2Score :: Accessor Score Int
 -- > p2Score = Accessor p2Score_ (\x s -> s { p2Score_ = x })
 --
+-- It is used with Template Haskell syntax like:
+--
+-- > $( deriveAccessors ''TypeName )
+--
+-- And will generate accessors when TypeName was declared
+-- using @data@ or @newtype@.
 deriveAccessors :: Name -> Q [Dec]
 deriveAccessors n = nameDeriveAccessors n transformName
     where
@@ -58,10 +64,29 @@
 -- field.
 nameDeriveAccessors :: Name -> (String -> Maybe String) -> Q [Dec]
 nameDeriveAccessors t namer = do
-    TyConI (DataD _ _name _ cons _) <- reify t
-    liftM concat $ mapM makeAccs cons
+    info <- reify t
+    reified <- case info of
+                    TyConI dec -> return dec
+                    _ -> fail errmsg
+    cons <- case reified of
+                 DataD _ _ _ cons' _ -> return cons'
+                 NewtypeD _ _ _ con' _ -> return [con']
+                 _ -> fail errmsg
+    decs <- liftM concat $ mapM makeAccs cons
+    when (null decs) $ qReport False nodefmsg
+    return decs
 
     where
+
+    errmsg = "Cannot derive accessors for name " ++ show t ++ " because"
+          ++ "\n    it is not a type declared with 'data' or 'newtype'"
+          ++ "\n    Did you remember to double-tick the type as in"
+          ++ "\n      $(deriveAccessors ''TheType)?"
+
+    nodefmsg = "Warning: No accessors generated from the name " ++ show t
+          ++ "\n    If you are using deriveAccessors rather than"
+          ++ "\n    nameDeriveAccessors, remember accessors are"
+          ++ "\n    only generated for fields ending with an underscore"
 
     makeAccs :: Con -> Q [Dec]
     makeAccs (RecC _ vars) =