diff --git a/Data/Stream.hs b/Data/Stream.hs
--- a/Data/Stream.hs
+++ b/Data/Stream.hs
@@ -14,6 +14,9 @@
    -- * Stream transformations
    , map
    , intersperse 
+   , interleave
+   , scanl
+   , scanl1
    -- * Building streams
    , iterate
    , repeat
@@ -48,7 +51,8 @@
    )
    where
 
-import Prelude hiding (head, tail, map, iterate, take, drop, takeWhile,
+import Prelude hiding (head, tail, map, scanl, scanl1,
+  iterate, take, drop, takeWhile,
   dropWhile, repeat, cycle, filter, (!!), zip, unzip,
   zipWith,words,unwords,lines,unlines, break, span, splitAt)
 
@@ -90,6 +94,13 @@
 intersperse :: a -> Stream a -> Stream a
 intersperse y (Cons x xs) = Cons x (Cons y (intersperse y xs))
 
+-- | Interleave two Streams @xs@ and @ys@, alternating elements
+-- from each list.
+--
+-- > @[x1,x2,...] `interleave` [y1,y2,...] == [x1,y1,x2,y2,...]@
+interleave :: Stream a -> Stream a -> Stream a
+interleave (Cons x xs) ys = Cons x (interleave ys xs)
+
 -- | Apply a function uniformly over all elements of a sequence.
 map :: (a -> b) -> Stream a -> Stream b
 map f (Cons x xs) = Cons (f x) (map f xs)
@@ -107,6 +118,19 @@
 -- > iterate f x = [x, f x, f (f x), ..]
 iterate :: (a -> a) -> a -> Stream a
 iterate f x = Cons x (iterate f (f x))
+
+-- | 'scanl' yields a stream of successive reduced values from the
+-- | left:
+-- 
+-- > scanl f z [x1, x2, ...] == [z, z `f` x1, (z `f` x1) `f` x2, ...]
+scanl :: (a -> b -> a) -> a -> Stream b -> Stream a
+scanl f z (Cons x xs) =  z <:> scanl f (f z x) xs
+
+-- | 'scanl1' is a variant of 'scanl' that has no starting value argument:
+--
+-- > scanl1 f [x1, x2, ...] == [x1, x1 `f` x2, ...]
+scanl1 :: (a -> a -> a) -> Stream a -> Stream a
+scanl1 f (Cons x xs) = scanl f x xs
 
 -- | 'take' @n@ @xs@ returns the first @n@ elements of @xs@.
 -- 
diff --git a/Stream.cabal b/Stream.cabal
--- a/Stream.cabal
+++ b/Stream.cabal
@@ -1,14 +1,14 @@
-Name:		        Stream
-Version:        	0.2.1
-License:        	BSD3
-License-file:		LICENSE
-Author:			Wouter Swierstra
-Maintainer:     	Wouter Swierstra <wss@cs.nott.ac.uk>
-Homepage:       	http://www.cs.nott.ac.uk/~wss/repos/Stream/dist/doc/html/
-Synopsis:       	A library for manipulating infinite lists.
-Description: 		This package implements functions, analogous
-			to those from Data.List, to create and manipulate infinite lists.
-Category:       	Data
-Build-Depends:  	base
-Exposed-modules:	Data.Stream
+Name:                   Stream
+Version:                0.2.2
+License:                BSD3
+License-file:           LICENSE
+Author:                 Wouter Swierstra
+Maintainer:             Wouter Swierstra <wss@cs.nott.ac.uk>
+Homepage:               http://www.cs.nott.ac.uk/~wss/repos/Stream/dist/doc/html/
+Synopsis:               A library for manipulating infinite lists.
+Description:            This package implements functions, analogous
+                        to those from Data.List, to create and manipulate infinite lists.
+Category:               Data
+Build-Depends:          base
+Exposed-modules:        Data.Stream