diff --git a/benchmarks/Main.hs b/benchmarks/Main.hs
--- a/benchmarks/Main.hs
+++ b/benchmarks/Main.hs
@@ -1,12 +1,12 @@
 module Main where
 
-import Prelude
+import Prelude hiding (concat)
 import Criterion.Main
 import ByteString.StrictBuilder
 
 
 main =
-  defaultMain [leftAppends, rightAppends]
+  defaultMain [leftAppends, rightAppends, concat]
 
 leftAppends :: Benchmark
 leftAppends =
@@ -27,3 +27,10 @@
       where
         builder =
           foldr (<>) mempty bytesList
+
+concat :: Benchmark
+concat =
+  bench "concat"  $ whnf action $! replicate 10000 $ bytes "abc"
+  where
+    action bytesList =
+      builderBytes (mconcat bytesList)
diff --git a/bytestring-strict-builder.cabal b/bytestring-strict-builder.cabal
--- a/bytestring-strict-builder.cabal
+++ b/bytestring-strict-builder.cabal
@@ -1,7 +1,7 @@
 name:
   bytestring-strict-builder
 version:
-  0.4.2
+  0.4.3
 category:
   Text, ByteString, Builders, Serialization
 synopsis:
@@ -9,9 +9,9 @@
 description:
   According to 
   <https://github.com/nikita-volkov/bytestring-builders-benchmark the competition benchmarks>, 
-  this library provides the fastest builder of strict bytestrings. 
+  this library provides on average the fastest builder of strict bytestrings. 
   .
-  Practical benchmarks have proven it to be highly performant aswell.
+  Practical benchmarks have proven it to be highly performant as well.
   The encoders from the \"postgresql-binary\" library have shown
   a stable performance improvement by factors of up to 10 after the migration
   from the standard builder to \"bytestring-strict-builder\".
@@ -56,7 +56,7 @@
     ByteString.StrictBuilder.UTF8
   build-depends:
     semigroups >= 0.18 && < 0.19,
-    bytestring >= 0.10 && < 0.11,
+    bytestring >= 0.10.2 && < 0.11,
     base-prelude >= 1.2 && < 2,
     base >= 4.6 && < 5
 
diff --git a/library/ByteString/StrictBuilder.hs b/library/ByteString/StrictBuilder.hs
--- a/library/ByteString/StrictBuilder.hs
+++ b/library/ByteString/StrictBuilder.hs
@@ -40,6 +40,14 @@
   {-# INLINE mappend #-}
   mappend (Builder leftSize leftPopulation) (Builder rightSize rightPopulation) =
     Builder (leftSize + rightSize) (leftPopulation <> rightPopulation)
+  {-# INLINE mconcat #-}
+  mconcat builders =
+    Builder size population
+    where
+      size =
+        getSum (foldMap (\(Builder x _) -> Sum x) builders)
+      population =
+        foldMap (\(Builder _ x) -> x) builders
 
 instance Semigroup Builder