diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9b9f30b6..161e66c2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
 * Support for `Accept`/`Content-type` headers and for the content-type aware combinators in *servant-0.3*
 * Export `toApplication` from `Servant.Server` (https://github.com/haskell-servant/servant-server/pull/29)
 * Support other Monads than just `EitherT (Int, String) IO` (https://github.com/haskell-servant/servant-server/pull/21)
+* Canonicalize API types before generating the handler types with `Server`
 * Make methods return status code 204 if they return () (https://github.com/haskell-servant/servant-server/issues/28)
 * Add server support for response headers
 
diff --git a/src/Servant/Server.hs b/src/Servant/Server.hs
index de5d8434..5489de3d 100644
--- a/src/Servant/Server.hs
+++ b/src/Servant/Server.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE TypeFamilies #-}
+{-# LANGUAGE FlexibleContexts #-}
 {-# LANGUAGE OverloadedStrings #-}
 
 -- | This module lets you implement 'Server's for defined APIs. You'll
@@ -13,11 +14,12 @@ module Servant.Server
   , -- * Handlers for all standard combinators
     HasServer(..)
   , Server
+  , ServerT
   ) where
 
 import Data.Proxy (Proxy)
 import Network.Wai (Application)
-
+import Servant.API (Canonicalize, canonicalize)
 import Servant.Server.Internal
 
 
@@ -43,5 +45,5 @@ import Servant.Server.Internal
 -- >
 -- > main :: IO ()
 -- > main = Network.Wai.Handler.Warp.run 8080 app
-serve :: HasServer layout => Proxy layout -> Server layout -> Application
-serve p server = toApplication (route p server)
+serve :: HasServer (Canonicalize layout) => Proxy layout -> Server layout -> Application
+serve p server = toApplication (route (canonicalize p) server)
diff --git a/src/Servant/Server/Internal.hs b/src/Servant/Server/Internal.hs
index 9e64dafc..6c509fe8 100644
--- a/src/Servant/Server/Internal.hs
+++ b/src/Servant/Server/Internal.hs
@@ -32,17 +32,17 @@ import           Network.Wai                 (Application, Request, Response,
                                               requestMethod, responseLBS,
                                               strictRequestBody)
 import           Servant.API                 ((:<|>) (..), (:>), Capture,
-                                              Delete, Get, Header, MatrixFlag,
-                                              MatrixParam, MatrixParams, Patch,
-                                              Post, Put, QueryFlag, QueryParam,
-                                              QueryParams, Raw, ReqBody)
+                                              Canonicalize, Delete, Get, Header,
+                                              MatrixFlag, MatrixParam, MatrixParams,
+                                              Patch, Post, Put, QueryFlag,
+                                              QueryParam, QueryParams, Raw,
+                                              ReqBody)
 import           Servant.API.ContentTypes    (AcceptHeader (..),
                                               AllCTRender (..),
                                               AllCTUnrender (..))
 import           Servant.API.ResponseHeaders (Headers, getResponse, getHeaders)
 import           Servant.Common.Text         (FromText, fromText)
 
-
 data ReqBodyState = Uncalled
                   | Called !B.ByteString
                   | Done !B.ByteString
@@ -168,11 +168,13 @@ processedPathInfo r =
   where pinfo = parsePathInfo r
 
 class HasServer layout where
-  type ServerT layout (m :: * -> *) :: *
-  route :: Proxy layout -> Server layout -> RoutingApplication
+  type ServerT' layout (m :: * -> *) :: *
 
-type Server layout = ServerT layout (EitherT (Int, String) IO)
+  route :: Proxy layout -> Server' layout -> RoutingApplication
 
+type Server layout = Server' (Canonicalize layout)
+type Server' layout = ServerT' layout (EitherT (Int, String) IO)
+type ServerT layout m = ServerT' (Canonicalize layout) m
 
 -- * Instances
 
@@ -188,9 +190,11 @@ type Server layout = ServerT layout (EitherT (Int, String) IO)
 -- >   where listAllBooks = ...
 -- >         postBook book = ...
 instance (HasServer a, HasServer b) => HasServer (a :<|> b) where
-  type ServerT (a :<|> b) m = ServerT a m :<|> ServerT b m
+
+  type ServerT' (a :<|> b) m = ServerT' a m :<|> ServerT' b m
+
   route Proxy (a :<|> b) request respond =
-    route pa a request $ \ mResponse ->
+    route pa a request $ \mResponse ->
       if isMismatch mResponse
         then route pb b request $ \mResponse' -> respond (mResponse <> mResponse')
         else respond mResponse
@@ -221,8 +225,8 @@ captured _ = fromText
 instance (KnownSymbol capture, FromText a, HasServer sublayout)
       => HasServer (Capture capture a :> sublayout) where
 
-  type ServerT (Capture capture a :> sublayout) m =
-     a -> ServerT sublayout m
+  type ServerT' (Capture capture a :> sublayout) m =
+     a -> ServerT' sublayout m
 
   route Proxy subserver request respond = case processedPathInfo request of
     (first : rest)
@@ -248,7 +252,8 @@ instance (KnownSymbol capture, FromText a, HasServer sublayout)
 -- painlessly error out if the conditions for a successful deletion
 -- are not met.
 instance HasServer Delete where
-  type ServerT Delete m = m ()
+
+  type ServerT' Delete m = m ()
 
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodDelete = do
@@ -277,7 +282,9 @@ instance HasServer Delete where
 -- list.
 instance ( AllCTRender ctypes a
          ) => HasServer (Get ctypes a) where
-  type ServerT (Get ctypes a) m = m a
+
+  type ServerT' (Get ctypes a) m = m a
+
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodGet = do
         e <- runEitherT action
@@ -296,7 +303,7 @@ instance ( AllCTRender ctypes a
 
 -- '()' ==> 204 No Content
 instance HasServer (Get ctypes ()) where
-  type ServerT (Get ctypes ()) m = m ()
+  type ServerT' (Get ctypes ()) m = m ()
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodGet = do
         e <- runEitherT action
@@ -310,7 +317,7 @@ instance HasServer (Get ctypes ()) where
 
 -- Add response headers
 instance ( AllCTRender ctypes v ) => HasServer (Get ctypes (Headers h v)) where
-  type ServerT (Get ctypes (Headers h v)) m = m (Headers h v)
+  type ServerT' (Get ctypes (Headers h v)) m = m (Headers h v)
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodGet = do
       e <- runEitherT action
@@ -351,8 +358,8 @@ instance ( AllCTRender ctypes v ) => HasServer (Get ctypes (Headers h v)) where
 instance (KnownSymbol sym, FromText a, HasServer sublayout)
       => HasServer (Header sym a :> sublayout) where
 
-  type ServerT (Header sym a :> sublayout) m =
-    Maybe a -> ServerT sublayout m
+  type ServerT' (Header sym a :> sublayout) m =
+    Maybe a -> ServerT' sublayout m
 
   route Proxy subserver request respond = do
     let mheader = fromText . decodeUtf8 =<< lookup str (requestHeaders request)
@@ -375,7 +382,8 @@ instance (KnownSymbol sym, FromText a, HasServer sublayout)
 -- list.
 instance ( AllCTRender ctypes a
          ) => HasServer (Post ctypes a) where
-  type ServerT (Post ctypes a) m = m a
+
+  type ServerT' (Post ctypes a) m = m a
 
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodPost = do
@@ -394,7 +402,7 @@ instance ( AllCTRender ctypes a
     | otherwise = respond $ failWith NotFound
 
 instance HasServer (Post ctypes ()) where
-  type ServerT (Post ctypes ()) m = m ()
+  type ServerT' (Post ctypes ()) m = m ()
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodPost = do
         e <- runEitherT action
@@ -408,7 +416,7 @@ instance HasServer (Post ctypes ()) where
 
 -- Add response headers
 instance ( AllCTRender ctypes v ) => HasServer (Post ctypes (Headers h v)) where
-  type ServerT (Post ctypes (Headers h v)) m = m (Headers h v)
+  type ServerT' (Post ctypes (Headers h v)) m = m (Headers h v)
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodPost = do
       e <- runEitherT action
@@ -441,7 +449,8 @@ instance ( AllCTRender ctypes v ) => HasServer (Post ctypes (Headers h v)) where
 -- list.
 instance ( AllCTRender ctypes a
          ) => HasServer (Put ctypes a) where
-  type ServerT (Put ctypes a) m = m a
+
+  type ServerT' (Put ctypes a) m = m a
 
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodPut = do
@@ -460,7 +469,7 @@ instance ( AllCTRender ctypes a
     | otherwise = respond $ failWith NotFound
 
 instance HasServer (Put ctypes ()) where
-  type ServerT (Put ctypes ()) m = m ()
+  type ServerT' (Put ctypes ()) m = m ()
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodPut = do
         e <- runEitherT action
@@ -474,7 +483,7 @@ instance HasServer (Put ctypes ()) where
 
 -- Add response headers
 instance ( AllCTRender ctypes v ) => HasServer (Put ctypes (Headers h v)) where
-  type ServerT (Put ctypes (Headers h v)) m = m (Headers h v)
+  type ServerT' (Put ctypes (Headers h v)) m = m (Headers h v)
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodPut = do
       e <- runEitherT action
@@ -505,7 +514,7 @@ instance ( AllCTRender ctypes v ) => HasServer (Put ctypes (Headers h v)) where
 -- yielding status code 200 along the way.
 instance ( AllCTRender ctypes a
          ) => HasServer (Patch ctypes a) where
-  type ServerT (Patch ctypes a) m = m a
+  type ServerT' (Patch ctypes a) m = m a
 
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodPatch = do
@@ -524,7 +533,7 @@ instance ( AllCTRender ctypes a
     | otherwise = respond $ failWith NotFound
 
 instance HasServer (Patch ctypes ()) where
-  type ServerT (Patch ctypes ()) m = m ()
+  type ServerT' (Patch ctypes ()) m = m ()
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodPatch = do
         e <- runEitherT action
@@ -538,7 +547,7 @@ instance HasServer (Patch ctypes ()) where
 
 -- Add response headers
 instance ( AllCTRender ctypes v ) => HasServer (Patch ctypes (Headers h v)) where
-  type ServerT (Patch ctypes (Headers h v)) m = m (Headers h v)
+  type ServerT' (Patch ctypes (Headers h v)) m = m (Headers h v)
   route Proxy action request respond
     | pathIsEmpty request && requestMethod request == methodPatch = do
       e <- runEitherT action
@@ -580,8 +589,8 @@ instance ( AllCTRender ctypes v ) => HasServer (Patch ctypes (Headers h v)) wher
 instance (KnownSymbol sym, FromText a, HasServer sublayout)
       => HasServer (QueryParam sym a :> sublayout) where
 
-  type ServerT (QueryParam sym a :> sublayout) m =
-    Maybe a -> ServerT sublayout m
+  type ServerT' (QueryParam sym a :> sublayout) m =
+    Maybe a -> ServerT' sublayout m
 
   route Proxy subserver request respond = do
     let querytext = parseQueryText $ rawQueryString request
@@ -618,8 +627,8 @@ instance (KnownSymbol sym, FromText a, HasServer sublayout)
 instance (KnownSymbol sym, FromText a, HasServer sublayout)
       => HasServer (QueryParams sym a :> sublayout) where
 
-  type ServerT (QueryParams sym a :> sublayout) m =
-    [a] -> ServerT sublayout m
+  type ServerT' (QueryParams sym a :> sublayout) m =
+    [a] -> ServerT' sublayout m
 
   route Proxy subserver request respond = do
     let querytext = parseQueryText $ rawQueryString request
@@ -651,8 +660,8 @@ instance (KnownSymbol sym, FromText a, HasServer sublayout)
 instance (KnownSymbol sym, HasServer sublayout)
       => HasServer (QueryFlag sym :> sublayout) where
 
-  type ServerT (QueryFlag sym :> sublayout) m =
-    Bool -> ServerT sublayout m
+  type ServerT' (QueryFlag sym :> sublayout) m =
+    Bool -> ServerT' sublayout m
 
   route Proxy subserver request respond = do
     let querytext = parseQueryText $ rawQueryString request
@@ -694,8 +703,8 @@ parseMatrixText = parseQueryText
 instance (KnownSymbol sym, FromText a, HasServer sublayout)
       => HasServer (MatrixParam sym a :> sublayout) where
 
-  type ServerT (MatrixParam sym a :> sublayout) m =
-    Maybe a -> ServerT sublayout m
+  type ServerT' (MatrixParam sym a :> sublayout) m =
+    Maybe a -> ServerT' sublayout m
 
   route Proxy subserver request respond = case parsePathInfo request of
     (first : _)
@@ -732,8 +741,8 @@ instance (KnownSymbol sym, FromText a, HasServer sublayout)
 instance (KnownSymbol sym, FromText a, HasServer sublayout)
       => HasServer (MatrixParams sym a :> sublayout) where
 
-  type ServerT (MatrixParams sym a :> sublayout) m =
-    [a] -> ServerT sublayout m
+  type ServerT' (MatrixParams sym a :> sublayout) m =
+    [a] -> ServerT' sublayout m
 
   route Proxy subserver request respond = case parsePathInfo request of
     (first : _)
@@ -766,8 +775,8 @@ instance (KnownSymbol sym, FromText a, HasServer sublayout)
 instance (KnownSymbol sym, HasServer sublayout)
       => HasServer (MatrixFlag sym :> sublayout) where
 
-  type ServerT (MatrixFlag sym :> sublayout) m =
-    Bool -> ServerT sublayout m
+  type ServerT' (MatrixFlag sym :> sublayout) m =
+    Bool -> ServerT' sublayout m
 
   route Proxy subserver request respond =  case parsePathInfo request of
     (first : _)
@@ -794,7 +803,9 @@ instance (KnownSymbol sym, HasServer sublayout)
 -- > server :: Server MyApi
 -- > server = serveDirectory "/var/www/images"
 instance HasServer Raw where
-  type ServerT Raw m = Application
+
+  type ServerT' Raw m = Application
+
   route Proxy rawApplication request respond =
     rawApplication request (respond . succeedWith)
 
@@ -821,8 +832,8 @@ instance HasServer Raw where
 instance ( AllCTUnrender list a, HasServer sublayout
          ) => HasServer (ReqBody list a :> sublayout) where
 
-  type ServerT (ReqBody list a :> sublayout) m =
-    a -> ServerT sublayout m
+  type ServerT' (ReqBody list a :> sublayout) m =
+    a -> ServerT' sublayout m
 
   route Proxy subserver request respond = do
     -- See HTTP RFC 2616, section 7.2.1
@@ -841,7 +852,9 @@ instance ( AllCTUnrender list a, HasServer sublayout
 -- | Make sure the incoming request starts with @"/path"@, strip it and
 -- pass the rest of the request path to @sublayout@.
 instance (KnownSymbol path, HasServer sublayout) => HasServer (path :> sublayout) where
-  type ServerT (path :> sublayout) m = ServerT sublayout m
+
+  type ServerT' (path :> sublayout) m = ServerT' sublayout m
+
   route Proxy subserver request respond = case processedPathInfo request of
     (first : rest)
       | first == cs (symbolVal proxyPath)
diff --git a/src/Servant/Utils/StaticFiles.hs b/src/Servant/Utils/StaticFiles.hs
index 9cd5fdcc..07c51173 100644
--- a/src/Servant/Utils/StaticFiles.hs
+++ b/src/Servant/Utils/StaticFiles.hs
@@ -9,7 +9,7 @@ module Servant.Utils.StaticFiles (
 import Filesystem.Path.CurrentOS (decodeString)
 import Network.Wai.Application.Static (staticApp, defaultFileServerSettings)
 import Servant.API.Raw (Raw)
-import Servant.Server.Internal (Server)
+import Servant.Server (Server)
 
 -- | Serve anything under the specified directory as a 'Raw' endpoint.
 --