diff --git a/CHANGELOG.markdown b/CHANGELOG.markdown
--- a/CHANGELOG.markdown
+++ b/CHANGELOG.markdown
@@ -1,3 +1,11 @@
+4.3
+---
+* Inverted dependency between `free` and `either`.
+
+4.2
+---
+* Added instances for `MonadThrow`, `MonadCatch`.
+
 4.1
 ---
 * Added instances for `MonadBase`, `MonadBaseControl`, and `MonadTransControl`.
diff --git a/either.cabal b/either.cabal
--- a/either.cabal
+++ b/either.cabal
@@ -1,6 +1,6 @@
 name:          either
 category:      Control, Monads
-version:       4.1.2
+version:       4.3
 license:       BSD3
 cabal-version: >= 1.6
 license-file:  LICENSE
@@ -28,13 +28,15 @@
 library
   build-depends:
     base              >= 4       && < 5,
-    monad-control     >= 0.3.2,
+    exceptions        >= 0.5     && < 0.7,
+    free              >= 4.9     && < 5,
+    monad-control     >= 0.3.2   && < 0.4,
     MonadRandom       == 0.1.*,
     mtl               >= 2.0     && < 2.3,
     semigroups        >= 0.8.3.1 && < 1,
     semigroupoids     >= 4       && < 5,
     transformers      >= 0.2     && < 0.5,
-    transformers-base >= 0.4
+    transformers-base >= 0.4     && < 0.5
 
   extensions: CPP
   exposed-modules: Control.Monad.Trans.Either
diff --git a/src/Control/Monad/Trans/Either.hs b/src/Control/Monad/Trans/Either.hs
--- a/src/Control/Monad/Trans/Either.hs
+++ b/src/Control/Monad/Trans/Either.hs
@@ -36,6 +36,8 @@
 import Control.Monad.Base (MonadBase(..), liftBaseDefault)
 import Control.Monad.Cont.Class
 import Control.Monad.Error.Class
+import Control.Monad.Free.Class
+import Control.Monad.Catch
 import Control.Monad.Fix
 import Control.Monad.IO.Class
 import Control.Monad.Reader.Class
@@ -195,7 +197,6 @@
   fail = EitherT . fail
   {-# INLINE fail #-}
 
-
 instance Monad m => MonadError e (EitherT e m) where
   throwError = EitherT . return . Left
   {-# INLINE throwError #-}
@@ -204,6 +205,16 @@
     Right r -> return (Right r)
   {-# INLINE catchError #-}
 
+-- | Throws exceptions into the base monad.
+instance MonadThrow m => MonadThrow (EitherT e m) where
+  throwM = lift . throwM
+  {-# INLINE throwM #-}
+
+-- | Catches exceptions from the base monad.
+instance MonadCatch m => MonadCatch (EitherT e m) where
+  catch (EitherT m) f = EitherT $ catch m (runEitherT . f)
+  {-# INLINE catch #-}
+
 instance MonadFix m => MonadFix (EitherT e m) where
   mfix f = EitherT $ mfix $ \a -> runEitherT $ f $ case a of
     Right r -> r
@@ -263,6 +274,9 @@
 instance Foldable m => Foldable (EitherT e m) where
   foldMap f = foldMap (either mempty f) . runEitherT
   {-# INLINE foldMap #-}
+
+instance (Functor f, MonadFree f m) => MonadFree f (EitherT e m) where
+  wrap = EitherT . wrap . fmap runEitherT
 
 instance (Monad f, Traversable f) => Traversable (EitherT e f) where
   traverse f (EitherT a) =