diff --git a/Database/Sql/Simple.hs b/Database/Sql/Simple.hs
--- a/Database/Sql/Simple.hs
+++ b/Database/Sql/Simple.hs
@@ -16,6 +16,7 @@
     , I.Sql
     , I.Elem
     , I.Backend
+    , I.Transaction
       -- * connection
     , I.ConnectInfo
     , I.withConnection
@@ -77,10 +78,10 @@
          => b -> I.Query -> (r -> IO ()) -> IO ()
 forEach_ = I.forEach_
 
-begin, commit, rollback :: I.Backend b => b -> I.Sql bs ()
+begin, commit, rollback :: I.Transaction b => b -> I.Sql bs ()
 begin = I.begin
 commit = I.commit
 rollback = I.rollback
 
-withTransaction :: I.Backend b => b -> I.Sql bs a -> I.Sql bs a
+withTransaction :: I.Transaction b => b -> I.Sql bs a -> I.Sql bs a
 withTransaction = I.withTransaction
diff --git a/Database/Sql/Simple/Internal.hs b/Database/Sql/Simple/Internal.hs
--- a/Database/Sql/Simple/Internal.hs
+++ b/Database/Sql/Simple/Internal.hs
@@ -14,8 +14,11 @@
 module Database.Sql.Simple.Internal where
 
 import GHC.Exts (Constraint)
+import Control.Monad
 import Control.Monad.Catch
 import Control.Monad.IO.Class
+import Control.Monad.Base
+import Control.Monad.Trans.Control
 import Control.Applicative
 
 import qualified Data.Text as T
@@ -28,8 +31,14 @@
     deriving (Show, Eq)
 
 newtype Sql (l :: [*]) a = Sql { unSql :: IO a }
-    deriving (Functor, Applicative, Monad, MonadIO, MonadThrow, MonadCatch, MonadMask)
+    deriving (Functor, Applicative, Monad, MonadIO, MonadThrow, MonadCatch, MonadMask, MonadBase IO)
 
+instance MonadBaseControl IO (Sql l) where
+    newtype StM (Sql l) a = StMSql { unStMSql :: StM IO a }
+    liftBaseWith f = Sql $ 
+        liftBaseWith (\run -> f $ liftM StMSql . run . unSql)
+    restoreM = Sql . restoreM . unStMSql
+
 instance IsString Query where
     fromString s = Query (T.pack s) H.empty
 
@@ -75,6 +84,7 @@
     forEach_ :: FromRow b r => b -> Query -> (r -> IO ()) -> IO ()
     forEach_ c q    = fold_ c q () . const
   
+class Backend b => Transaction b where
     begin    :: b -> Sql c ()
     commit   :: b -> Sql c ()
     rollback :: b -> Sql c ()
diff --git a/sql-simple.cabal b/sql-simple.cabal
--- a/sql-simple.cabal
+++ b/sql-simple.cabal
@@ -1,5 +1,5 @@
 name:                sql-simple
-version:             0.2.0
+version:             0.3.0
 synopsis:            common middle-level sql client.
 description:         please read README.md <https://github.com/philopon/sql-simple/blob/master/README.md>
 license:             MIT
@@ -22,6 +22,8 @@
                      , text                 >=1.1 && <1.2
                      , transformers         >=0.4 && <0.5
                      , unordered-containers >=0.2 && <0.3
+                     , monad-control        >=0.3 && <0.4
+                     , transformers-base    >=0.4 && <0.5
 
   if impl(ghc < 7.8)
     build-depends:     tagged               >=0.7 && <0.8