diff --git a/lib/Crypt/KeyDerivation.pm b/lib/Crypt/KeyDerivation.pm
index 5d6d87a..696cbbe 100644
--- a/lib/Crypt/KeyDerivation.pm
+++ b/lib/Crypt/KeyDerivation.pm
@@ -22,6 +22,8 @@
 Crypt::KeyDerivation - PBKDF1, PBKDF2 and HKDF key derivation functions
 
 =head1 SYNOPSIS
+
+  use Crypt::KeyDerivation ':all';
 
   ### PBKDF1/2
   $derived_key1 = pbkdf1($password, $salt, $iteration_count, $hash_name, $len);