diff --git a/yesod-core/Yesod/Handler.hs b/yesod-core/Yesod/Handler.hs
index 04688af4..0e355161 100644
--- a/yesod-core/Yesod/Handler.hs
+++ b/yesod-core/Yesod/Handler.hs
@@ -155,6 +155,7 @@ import Control.Arrow ((***))
 import qualified Network.Wai.Parse as NWP
 import Data.Monoid (mappend, mempty, Endo (..))
 import qualified Data.ByteString.Char8 as S8
+import Data.ByteString (ByteString)
 import Data.CaseInsensitive (CI)
 import qualified Data.CaseInsensitive as CI
 import Blaze.ByteString.Builder (toByteString)
@@ -808,7 +809,7 @@ handlerToYAR y s upload log' toMasterRoute render errorHandler rr murl sessionMa
     types = httpAccept $ reqWaiRequest rr
     errorHandler' = localNoCurrent . errorHandler
 
-yarToResponse :: YesodAppResult -> [(CI H.Ascii, H.Ascii)] -> W.Response
+yarToResponse :: YesodAppResult -> [(CI ByteString, ByteString)] -> W.Response
 yarToResponse (YARWai a) _ = a
 yarToResponse (YARPlain s hs _ c _) extraHeaders =
     case c of
@@ -830,7 +831,7 @@ httpAccept = parseHttpAccept
 
 -- | Convert Header to a key/value pair.
 headerToPair :: Header
-             -> (CI H.Ascii, H.Ascii)
+             -> (CI ByteString, ByteString)
 headerToPair (AddCookie sc) =
     ("Set-Cookie", toByteString $ renderSetCookie $ sc)
 headerToPair (DeleteCookie key path) =
diff --git a/yesod-core/Yesod/Internal.hs b/yesod-core/Yesod/Internal.hs
index 33715489..05f26798 100644
--- a/yesod-core/Yesod/Internal.hs
+++ b/yesod-core/Yesod/Internal.hs
@@ -42,8 +42,8 @@ import qualified Network.HTTP.Types as H
 import Data.String (IsString)
 import qualified Data.Map as Map
 import Data.Text.Lazy.Builder (Builder)
-import Network.HTTP.Types (Ascii)
 import Web.Cookie (SetCookie (..))
+import Data.ByteString (ByteString)
 
 -- | Responses to indicate some form of an error occurred. These are different
 -- from 'SpecialResponse' in that they allow for custom error pages.
@@ -60,8 +60,8 @@ instance Exception ErrorResponse
 -- | Headers to be added to a 'Result'.
 data Header =
     AddCookie SetCookie
-    | DeleteCookie Ascii Ascii
-    | Header Ascii Ascii
+    | DeleteCookie ByteString ByteString
+    | Header ByteString ByteString
     deriving (Eq, Show)
 
 langKey :: IsString a => a
diff --git a/yesod-core/yesod-core.cabal b/yesod-core/yesod-core.cabal
index 0a8fa555..c19b3333 100644
--- a/yesod-core/yesod-core.cabal
+++ b/yesod-core/yesod-core.cabal
@@ -71,7 +71,7 @@ library
                    , monad-control         >= 0.3      && < 0.4
                    , transformers-base     >= 0.4
                    , cookie                >= 0.4      && < 0.5
-                   , http-types            >= 0.6.5    && < 0.7
+                   , http-types            >= 0.7      && < 0.8
                    , case-insensitive      >= 0.2
                    , parsec                >= 2        && < 3.2
                    , directory             >= 1        && < 1.2
diff --git a/yesod-static/yesod-static.cabal b/yesod-static/yesod-static.cabal
index cf39f1c8..84a9fe38 100644
--- a/yesod-static/yesod-static.cabal
+++ b/yesod-static/yesod-static.cabal
@@ -30,7 +30,7 @@ library
                    , wai                   >= 1.3      && < 1.4
                    , text                  >= 0.9      && < 1.0
                    , file-embed            >= 0.0.4.1  && < 0.5
-                   , http-types            >= 0.6.5    && < 0.7
+                   , http-types            >= 0.7      && < 0.8
                    , unix-compat           >= 0.2
                    , conduit               >= 0.5      && < 0.6
                    , crypto-conduit        >= 0.4      && < 0.5
@@ -61,7 +61,7 @@ test-suite tests
                    , wai
                    , text                  >= 0.9      && < 1.0
                    , file-embed            >= 0.0.4.1  && < 0.5
-                   , http-types            >= 0.6.5    && < 0.7
+                   , http-types
                    , unix-compat           >= 0.2
                    , conduit
                    , crypto-conduit
diff --git a/yesod-test/Yesod/Test.hs b/yesod-test/Yesod/Test.hs
index 312eb889..5d8c371f 100644
--- a/yesod-test/Yesod/Test.hs
+++ b/yesod-test/Yesod/Test.hs
@@ -69,6 +69,7 @@ import qualified Test.Hspec.Runner as Runner
 import qualified Data.List as DL
 import qualified Data.Maybe as DY
 import qualified Data.ByteString.Char8 as BS8
+import Data.ByteString (ByteString)
 import qualified Data.Text as T
 import qualified Data.Text.Encoding as TE
 import qualified Data.ByteString.Lazy.Char8 as BSL8
@@ -123,7 +124,7 @@ instance HoldsResponse OneSpecData where
 instance HoldsResponse RequestBuilderData where
   readResponse (RequestBuilderData _ x) = x
   
-type CookieValue = H.Ascii
+type CookieValue = ByteString
 
 -- | Runs your test suite, using you wai 'Application' and 'ConnectionPool' for performing 
 -- the database queries in your tests.
diff --git a/yesod-test/yesod-test.cabal b/yesod-test/yesod-test.cabal
index 793e5d93..758e10c1 100644
--- a/yesod-test/yesod-test.cabal
+++ b/yesod-test/yesod-test.cabal
@@ -22,7 +22,7 @@ library
                    , wai                       >= 1.3      && < 1.4
                    , wai-test                  >= 1.3      && < 1.4
                    , network                   >= 2.2      && < 2.4
-                   , http-types                >= 0.6      && < 0.7
+                   , http-types                >= 0.7      && < 0.8
                    , HUnit                     >= 1.2      && < 1.3
                    , hspec                     >= 1.2      && < 1.3
                    , bytestring                >= 0.9
diff --git a/yesod/yesod.cabal b/yesod/yesod.cabal
index 3316aa32..45fcc303 100644
--- a/yesod/yesod.cabal
+++ b/yesod/yesod.cabal
@@ -99,7 +99,7 @@ executable             yesod
                      , unix-compat        >= 0.2          && < 0.4
                      , containers         >= 0.2
                      , attoparsec         >= 0.10
-                     , http-types         >= 0.6.1        && < 0.7
+                     , http-types         >= 0.7          && < 0.8
                      , blaze-builder      >= 0.2.1.4      && < 0.4
                      , filepath           >= 1.1
                      , process