diff --git a/src/Servant/Multipart.hs b/src/Servant/Multipart.hs
index 68aae04..6423193 100644
--- a/src/Servant/Multipart.hs
+++ b/src/Servant/Multipart.hs
@@ -173,6 +173,12 @@ data MultipartData tag = MultipartData
   , files  :: [FileData tag]
   }
 
+instance Semigroup (MultipartData tag) where
+  d1 <> d2 = MultipartData (inputs d1 <> inputs d2) (files d1 <> files d2)
+
+instance Monoid (MultipartData tag) where
+  mempty = MultipartData [] []
+
 fromRaw :: forall tag. ([Network.Wai.Parse.Param], [File (MultipartResult tag)])
         -> MultipartData tag
 fromRaw (inputs, files) = MultipartData is fs
@@ -274,6 +280,9 @@ class ToMultipart tag a where
 instance ToMultipart tag (MultipartData tag) where
   toMultipart = id
 
+instance (ToMultipart tag a, Foldable t) => ToMultipart tag (t a) where
+  toMultipart xs = foldMap toMultipart xs
+
 -- | Upon seeing @MultipartForm a :> ...@ in an API type,
 ---  servant-server will hand a value of type @a@ to your handler
 --   assuming the request body's content type is