diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -2,6 +2,8 @@
 
 ## Unreleased changes
 
+## 0.1.4
+
 ## 0.1.3
 
 * Fix tests on older LTS
diff --git a/appendmap.cabal b/appendmap.cabal
--- a/appendmap.cabal
+++ b/appendmap.cabal
@@ -2,10 +2,10 @@
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 15eb223caaae1746fc5120f20c2e474df8b597f8c481c9d0dd3d8e2ebdd715fc
+-- hash: da3c92d32d8763def130a63fd3d7770833e6f5a30a50b0a56e8d011019a440ec
 
 name:           appendmap
-version:        0.1.3
+version:        0.1.4
 synopsis:       Map with a Semigroup and Monoid instances delegating to Semigroup of the elements
 description:    Please see the README on GitHub at <https://github.com/koterpillar/appendmap#readme>
 category:       Data Structures
@@ -31,6 +31,7 @@
       Data.Map.Append
       Data.Map.Append.Lazy
       Data.Map.Append.Strict
+      Data.Map.Counter
   other-modules:
       Paths_appendmap
   hs-source-dirs:
diff --git a/src/Data/Map/Counter.hs b/src/Data/Map/Counter.hs
new file mode 100644
--- /dev/null
+++ b/src/Data/Map/Counter.hs
@@ -0,0 +1,15 @@
+module Data.Map.Counter where
+
+import           Data.Map.Append.Strict
+import           Data.Map.Strict        (Map)
+import qualified Data.Map.Strict        as Map
+
+import           Data.Monoid
+
+type Counter key = AppendMap key (Sum Int)
+
+mkCounter :: Ord key => key -> Counter key
+mkCounter key = AppendMap $ Map.singleton key (Sum 1)
+
+getCounts :: Counter key -> Map key Int
+getCounts = Map.map getSum . unAppendMap
diff --git a/test/Spec.hs b/test/Spec.hs
--- a/test/Spec.hs
+++ b/test/Spec.hs
@@ -1,6 +1,6 @@
-{-# LANGUAGE AllowAmbiguousTypes    #-}
-{-# LANGUAGE RankNTypes             #-}
-{-# LANGUAGE RecordWildCards        #-}
+{-# LANGUAGE AllowAmbiguousTypes #-}
+{-# LANGUAGE RankNTypes          #-}
+{-# LANGUAGE RecordWildCards     #-}
 
 import qualified Data.Map.Append.Lazy   as Lazy
 import qualified Data.Map.Lazy          as Lazy
@@ -8,6 +8,8 @@
 import qualified Data.Map.Append.Strict as Strict
 import qualified Data.Map.Strict        as Strict
 
+import qualified Data.Map.Counter       as Counter
+
 import           Data.Semigroup
 
 import           Test.Hspec
@@ -46,15 +48,26 @@
   => AppendMap appendmap map
   -> Spec
 appendMapSpec AppendMap {..} = do
-  it "has empty element" $
-    unAppendMap mempty `shouldBe` mapEmpty
+  it "has empty element" $ unAppendMap mempty `shouldBe` mapEmpty
   it "combines elements" $ do
     let one = appendMap $ mapFromList [(1, "hello"), (2, "goodbye")]
     let two = appendMap $ mapFromList [(1, "world"), (3, "again")]
     unAppendMap (one <> two) `shouldBe`
       mapFromList [(1, "helloworld"), (2, "goodbye"), (3, "again")]
 
+counterSpec :: Spec
+counterSpec =
+  it "counts entries" $ do
+    let counted =
+          Counter.mkCounter "one" <> Counter.mkCounter "two" <>
+          Counter.mkCounter "two"
+    let result = Counter.getCounts counted
+    Strict.lookup "one" result `shouldBe` Just 1
+    Strict.lookup "two" result `shouldBe` Just 2
+
 main :: IO ()
-main = hspec $ do
-  describe "Data.Map.Append.Lazy" $ appendMapSpec lazy
-  describe "Data.Map.Append.Strict" $ appendMapSpec strict
+main =
+  hspec $ do
+    describe "Data.Map.Append.Lazy" $ appendMapSpec lazy
+    describe "Data.Map.Append.Strict" $ appendMapSpec strict
+    describe "Data.Map.Counter" counterSpec