diff --git a/src/Puppet/Interpreter/Resolve.hs b/src/Puppet/Interpreter/Resolve.hs
index ed1d3502..07d9176e 100644
--- a/src/Puppet/Interpreter/Resolve.hs
+++ b/src/Puppet/Interpreter/Resolve.hs
@@ -661,6 +661,7 @@ resolveDataType ud
       UDTScalar           -> pure DTScalar
       UDTData             -> pure DTData
       UDTOptional dt      -> DTOptional <$> resolveDataType dt
+      UDTSensitive dt     -> DTSensitive <$> resolveDataType dt
       UNotUndef           -> pure NotUndef
       UDTVariant vrs      -> DTVariant <$> traverse resolveDataType vrs
       UDTPattern a        -> pure (DTPattern a)
@@ -785,6 +786,7 @@ datatypeMatch dt v =
     DTScalar             -> datatypeMatch (DTVariant (DTInteger Nothing Nothing :| [DTString Nothing Nothing, DTBoolean])) v
     DTData               -> datatypeMatch (DTVariant (DTScalar :| [DTArray DTData 0 Nothing, DTHash DTScalar DTData 0 Nothing])) v
     DTOptional sdt       -> datatypeMatch (DTVariant (DTUndef :| [sdt])) v
+    DTSensitive sdt      -> datatypeMatch (DTVariant (DTUndef :| [sdt])) v
     DTVariant sdts       -> any (`datatypeMatch` v) sdts
     DTEnum lst           -> maybe False (`elem` lst) (v ^? _PString)
     DTAny                -> True
diff --git a/src/Puppet/Language/Value.hs b/src/Puppet/Language/Value.hs
index 16ed3bee..cca7d261 100644
--- a/src/Puppet/Language/Value.hs
+++ b/src/Puppet/Language/Value.hs
@@ -24,6 +24,7 @@ data DataType
     | DTScalar
     | DTData
     | DTOptional DataType
+    | DTSensitive DataType
     | NotUndef
     | DTVariant (NonEmpty DataType)
     | DTPattern (NonEmpty CompRegex)
@@ -45,6 +46,7 @@ instance Pretty DataType where
     DTScalar            -> "Scalar"
     DTData              -> "Data"
     DTOptional o        -> "Optional" <> brackets (pretty o)
+    DTSensitive o       -> "Sensitive" <> brackets (pretty o)
     NotUndef            -> "NotUndef"
     DTVariant vs        -> "Variant" <> list (foldMap (pure . pretty) vs)
     DTPattern vs        -> "Pattern" <> list (foldMap (pure . pretty) vs)
diff --git a/src/Puppet/Parser.hs b/src/Puppet/Parser.hs
index 76e349b6..712b429f 100644
--- a/src/Puppet/Parser.hs
+++ b/src/Puppet/Parser.hs
@@ -668,6 +668,7 @@ datatype = dtString
        <|> dtHash
        <|> (UDTUndef <$ reserved "Undef")
        <|> (reserved "Optional" *> (UDTOptional <$> brackets datatype))
+       <|> (reserved "Sensitive" *> (UDTSensitive <$> brackets datatype))
        <|> (UNotUndef <$ reserved "NotUndef")
        <|> (reserved "Variant" *> (UDTVariant . NE.fromList <$> brackets (datatype `sepBy1` symbolic ',')))
        -- while all the other cases are straightforward, it seems that the
diff --git a/src/Puppet/Parser/PrettyPrinter.hs b/src/Puppet/Parser/PrettyPrinter.hs
index 9bc18cec..6d352623 100644
--- a/src/Puppet/Parser/PrettyPrinter.hs
+++ b/src/Puppet/Parser/PrettyPrinter.hs
@@ -38,6 +38,7 @@ instance Pretty UDataType where
     UDTScalar            -> "Scalar"
     UDTData              -> "Data"
     UDTOptional o        -> "Optional" <> brackets (pretty o)
+    UDTSensitive o       -> "Sensitive" <> brackets (pretty o)
     UNotUndef            -> "NotUndef"
     UDTVariant vs        -> "Variant" <> list (foldMap (pure . pretty) vs)
     UDTPattern vs        -> "Pattern" <> list (foldMap (pure . pretty) vs)
diff --git a/src/Puppet/Parser/Types.hs b/src/Puppet/Parser/Types.hs
index f3c17bb9..2bbf3794 100644
--- a/src/Puppet/Parser/Types.hs
+++ b/src/Puppet/Parser/Types.hs
@@ -173,6 +173,7 @@ data UDataType
     | UDTScalar
     | UDTData
     | UDTOptional UDataType
+    | UDTSensitive UDataType
     | UNotUndef
     | UDTVariant (NonEmpty UDataType)
     | UDTPattern (NonEmpty CompRegex)
diff --git a/tests/DT/Parser.hs b/tests/DT/Parser.hs
index 0326dd76..8f23da61 100644
--- a/tests/DT/Parser.hs
+++ b/tests/DT/Parser.hs
@@ -18,3 +18,5 @@ spec = do
     it "accepts variables" $ pendingWith "to be fixed" *> parse datatype "?" "String[$var]" `shouldParse` UDTString (Just 5) Nothing
   describe "Stdlib::" $ do
     "Stdlib::HTTPUrl" `parsed` UDTData
+  describe "Sensitive" $ do
+    "Sensitive[String]" `parsed` UDTSensitive (UDTString Nothing Nothing)