diff --git a/CHANGES b/CHANGES
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,7 @@
+* 3000.11.4 (24 January 2020)
+
+  - Add support for <nil/> corresponding to unit () in Haskell
+
 * 3000.11.3.1 (17 December 2019)
 
   - Updates for GHC 8.8, network-3.1
diff --git a/Network/XmlRpc/DTD_XMLRPC.hs b/Network/XmlRpc/DTD_XMLRPC.hs
--- a/Network/XmlRpc/DTD_XMLRPC.hs
+++ b/Network/XmlRpc/DTD_XMLRPC.hs
@@ -21,6 +21,7 @@
 data Member = Member Name Value
             deriving (Eq,Show)
 newtype Struct = Struct [Member]                deriving (Eq,Show)
+newtype Nil = Nil ()                    deriving (Eq,Show)
 newtype Value = Value [Value_]          deriving (Eq,Show)
 data Value_ = Value_Str String
             | Value_I4 I4
@@ -33,6 +34,7 @@
             | Value_Base64 Base64
             | Value_Struct Struct
             | Value_Array Array
+            | Value_Nil Nil
             deriving (Eq,Show)
 newtype Param = Param Value             deriving (Eq,Show)
 newtype Params = Params [Param]                 deriving (Eq,Show)
@@ -118,6 +120,16 @@
                        `apply` (text `onFail` return "")
         } `adjustErr` ("in <dateTime.iso8601>, "++)
 
+instance HTypeable Nil where
+    toHType x = Defined "nil" [] []
+instance XmlContent Nil where
+    toContents (Nil a) =
+        [CElem (Elem (N "nil") [] []) ()]
+    parseContents = do
+        { e@(Elem _ [] _) <- element ["nil"]
+        ; interior e $ return (Nil) `apply` (return ())
+        } `adjustErr` ("in <nil/>, "++)
+
 instance HTypeable Base64 where
     toHType x = Defined "base64" [] []
 instance XmlContent Base64 where
@@ -203,6 +215,7 @@
     toContents (Value_Base64 a) = toContents a
     toContents (Value_Struct a) = toContents a
     toContents (Value_Array a) = toContents a
+    toContents (Value_Nil a) = toContents a
     parseContents = oneOf
         [ return (Value_Str) `apply` text
         , return (Value_I4) `apply` parseContents
@@ -215,6 +228,7 @@
         , return (Value_Base64) `apply` parseContents
         , return (Value_Struct) `apply` parseContents
         , return (Value_Array) `apply` parseContents
+        , return (Value_Nil) `apply` parseContents
         ] `adjustErr` ("in <value>, "++)
 
 instance HTypeable Param where
diff --git a/Network/XmlRpc/Internals.hs b/Network/XmlRpc/Internals.hs
--- a/Network/XmlRpc/Internals.hs
+++ b/Network/XmlRpc/Internals.hs
@@ -170,6 +170,7 @@
     | ValueBase64 BS.ByteString -- ^ base 64.  NOTE that you should provide the raw data; the haxr library takes care of doing the base-64 encoding.
     | ValueStruct [(String,Value)] -- ^ struct
     | ValueArray [Value]  -- ^ array
+    | ValueNil -- ^ nil
       deriving (Eq, Show) -- for debugging
 
 -- | An XML-RPC value. Use for error messages and introspection.
@@ -183,6 +184,7 @@
           | TStruct
           | TArray
           | TUnknown
+          | TNil
       deriving (Eq)
 
 instance Show Type where
@@ -195,6 +197,7 @@
     show TStruct = "struct"
     show TArray = "array"
     show TUnknown = "unknown"
+    show TNil = "nil"
 
 instance Read Type where
     readsPrec _ s = case break isSpace (dropWhile isSpace s) of
@@ -206,6 +209,7 @@
                     ("base64",r) -> [(TBase64,r)]
                     ("struct",r) -> [(TStruct,r)]
                     ("array",r) -> [(TArray,r)]
+                    ("nil",r) -> [(TNil,r)]
 
 -- | Gets the value of a struct member
 structGetValue :: MonadFail m => String -> Value -> Err m Value
@@ -319,6 +323,13 @@
     fromValue = liftM localTimeToCalendarTime . fromValue
     getType _ = TDateTime
 
+instance XmlRpcType () where
+    toValue = const ValueNil
+    fromValue = simpleFromValue f
+        where f ValueNil = Just ()
+              f _ = Nothing
+    getType _ = TNil
+
 -- FIXME: array elements may have different types
 instance OVERLAPPABLE_ XmlRpcType a => XmlRpcType [a] where
     toValue = ValueArray . map toValue
@@ -402,6 +413,7 @@
 toXRValue (ValueStruct xs) = XR.Value [XR.Value_Struct (XR.Struct (map toXRMember xs))]
 toXRValue (ValueArray xs) =
     XR.Value [XR.Value_Array (XR.Array (XR.Data (map toXRValue xs)))]
+toXRValue ValueNil = XR.Value [XR.Value_Nil (XR.Nil ())]
 
 showInt :: Int -> String
 showInt = show
@@ -467,6 +479,7 @@
     liftM ValueStruct (mapM fromXRMember ms)
   f (XR.Value_Array (XR.Array (XR.Data xs))) =
     liftM ValueArray (mapM fromXRValue xs)
+  f (XR.Value_Nil (XR.Nil x)) = return ValueNil
 
 
 fromXRMember :: MonadFail m => XR.Member -> Err m (String,Value)
diff --git a/haxr.cabal b/haxr.cabal
--- a/haxr.cabal
+++ b/haxr.cabal
@@ -1,5 +1,5 @@
 Name: haxr
-Version: 3000.11.3.1
+Version: 3000.11.4
 Cabal-version: >=1.10
 Build-type: Simple
 Copyright: Bjorn Bringert, 2003-2006
@@ -34,7 +34,7 @@
 
 Library
   Build-depends: base >= 4.9 && < 4.14,
-                 base-compat >= 0.8 && < 0.11,
+                 base-compat >= 0.8 && < 0.12,
                  mtl,
                  mtl-compat,
                  network < 3.2,