The MUG project common to eBES, eInV3 and BII2 has issued its in September 2011 CWAs on the Core European Invoice Message Implementation Guidelines (MUG project)
Background
The CEN WS/eBES is a focal point within Europe for the standardization of exchanging electronic business data. It is the 'European Entry point' for the UN-ECE/CEFACT electronic business standardization process based on XML format. We are also still maintaining traditional Electronic Data Interchange (EDI) standards.
WS/eBES therefore represents the European point of view in the global debate, including on the need for a multi-lingual and multi-cultural approach to B2B data interchange standardization.
The business plan (version 7.0) is available here: 
Business Plan
Working Groups information
A number of European Expert Groups work on specific issues relating to several processes or sectors.
Publications
How to become a Member
A fee is required for registering to the WS/eBES. It enables participation in the consensus process at the Workshop Plenary meetings (that is held three or four times a year) and at the other various WS activities.
Contact points
Chairman
Kevin Ginty, University of Sunderland
E-mail
Vice-Chair
Bernard Longhi, BLC Consultant
E-mail
Secretary
CEN-CENELEC Management Centre
Alain Dechamps
Electrotechnology & ICT
E-mail
Other