diff --git a/CHANGES.md b/CHANGES.md
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,6 +1,12 @@
 Changes
 =======
 
+Version 0.6.1
+-----------
+
+* Documentation improvements
+* Make the package build with GHC 7.4.1
+
 Version 0.6
 -----------
 
diff --git a/Test/SmallCheck/Series.hs b/Test/SmallCheck/Series.hs
--- a/Test/SmallCheck/Series.hs
+++ b/Test/SmallCheck/Series.hs
@@ -50,6 +50,21 @@
   --
   -- The depth of @Light x@ is just the depth of @x@.
 
+  -- ** What does consN do, exactly?
+
+  -- | @consN@ has type
+  -- @(Serial t_1, ..., Serial t_N) => (t_1 -> ... -> t_N -> t) -> Series t@.
+  --
+  -- @consN f@ is a series which, for a given depth @d > 0@, produces values of the
+  -- form
+  --
+  -- >f x_1 ... x_N
+  --
+  -- where @x_i@ ranges over all values of type @t_i@ of depth up to @d-1@
+  -- (as defined by the 'series' functions for @t_i@).
+  --
+  -- If @d <= 0@, no values are produced.
+
   cons0, cons1, cons2, cons3, cons4,
   -- * Function Generators
 
@@ -67,6 +82,23 @@
   -- >coseries rs d = [ \l -> case l of
   -- >                        Light x -> f x
   -- >                |  f <- (alts1 rs . depth 0) d ]
+
+  -- ** What does altsN do, exactly?
+
+  -- | @altsN@ has type
+  -- @(Serial t_1, ..., Serial t_N) => Series t -> Series (t_1 -> ... -> t_N -> t)@.
+  --
+  -- @altsN s@ is a series which, for a given depth @d@, produces functions of
+  -- type
+  --
+  -- >t_1 -> ... -> t_N -> t
+  --
+  -- If @d <= 0@, these are constant functions, one for each value of @s 0@.
+  --
+  -- If @d > 0@, these functions inspect each of their arguments up to depth
+  -- @d-1@ (as defined by the 'coseries' functions for the corresponding
+  -- types) and return values given by @s d@.
+
   alts0, alts1, alts2, alts3, alts4,
 
   -- * Automated Derivation of Generators
@@ -121,6 +153,10 @@
 type Depth = Int
 
 -- | 'Series' is a function from the depth to a finite list of values.
+--
+-- If @s@ is a 'Series', @s n@ is expected to yield values of depth up to @n@.
+--
+-- (In particular, @series d@ is expected to be a subset of @series (d+1)@.)
 type Series a = Depth -> [a]
 
 -- | Sum (union) of series
@@ -135,6 +171,9 @@
 
 class Serial a where
   series   :: Series a
+  -- | A proper 'coseries' implementation should pass the depth unchanged to
+  -- its first argument. Doing otherwise will make enumeration of curried
+  -- functions non-uniform in their arguments.
   coseries :: Series b -> Series (a->b)
 
 #ifdef GENERICS
diff --git a/smallcheck.cabal b/smallcheck.cabal
--- a/smallcheck.cabal
+++ b/smallcheck.cabal
@@ -1,5 +1,5 @@
 Name:          smallcheck
-Version:       0.6
+Version:       0.6.1
 Cabal-Version: >= 1.6
 License:       BSD3
 License-File:  LICENSE
@@ -39,7 +39,7 @@
 Source-repository this
   type:     git
   location: git://github.com/feuerbach/smallcheck.git
-  tag:      v0.6
+  tag:      v0.6.1
 
 Library