diff --git a/proteus/__init__.py b/proteus/__init__.py
index c8cd5efa8c..71c672342b 100644
--- a/proteus/__init__.py
+++ b/proteus/__init__.py
@@ -4,6 +4,7 @@
 A library to access Tryton's models like a client.
 '''
 __version__ = "0.0.1"
+__all__ = ['Model', 'Wizard']
 from types import NoneType
 import threading
 import datetime
diff --git a/proteus/config.py b/proteus/config.py
index fa1baef8d4..6a7b2a620b 100644
--- a/proteus/config.py
+++ b/proteus/config.py
@@ -4,6 +4,7 @@
 Configuration functions for the proteus package for Tryton.
 """
 from __future__ import with_statement
+__all__ = ['set_trytond', 'set_xmlrpc', 'get_config']
 import xmlrpclib
 import threading
 from decimal import Decimal
diff --git a/proteus/pyson.py b/proteus/pyson.py
index b3d375bb30..5eca3cb6a6 100644
--- a/proteus/pyson.py
+++ b/proteus/pyson.py
@@ -1,5 +1,7 @@
 #This file is part of Tryton.  The COPYRIGHT file at the top level of
 #this repository contains the full copyright notices and license terms.
+__all__ = ['PYSONEncoder', 'PYSONDecoder', 'Eval', 'Not', 'Bool', 'And', 'Or',
+        'Equal', 'Greater', 'Less', 'If', 'Get', 'In', 'Date', 'DateTime']
 import sys
 if sys.version_info < (2, 6):
     import simplejson as json