diff --git a/pyramid_oauthlib/__init__.py b/pyramid_oauthlib/__init__.py
index e5fd0c4..2d59f36 100644
--- a/pyramid_oauthlib/__init__.py
+++ b/pyramid_oauthlib/__init__.py
@@ -5,6 +5,7 @@
 from oauthlib import oauth2
 from oauthlib.oauth2.rfc6749.endpoints import base
 from pyramid.response import Response
+from pyramid.compat import bytes_
 
 log = logging.getLogger(__name__)
 
@@ -167,7 +168,11 @@ def getter(request):
 
 def oauth_response(result):  # pragma: no cover
     headers, body, status = result
-    return Response(body=body, status=status, headers=headers)
+    return Response(body=body, status=status, headers={
+        bytes_(name, 'utf-8'): bytes_(value, 'utf-8')
+        for name, value
+        in headers.iteritems()
+    })
 
 
 def register(config, server):