The Commission services (DG Information Society), in close cooperation with the EU's Dutch Presidency, held an open workshop on 15 November to assess progress in implementing anti-spam measures further to the Commission's January 2004 Communication on this issue. The workshop highlighted three key points. Most of the Member States have quickly transposed the privacy and electronic communications Directive into their national laws. Yet, the Commission in some cases will need to assess these laws carefully, to ascertain whether differences amongst them might represent an obstacle to effective cross-border enforcement. Another important conclusion is the changing nature of spam, from "unsolicited commercial communication", to a problem inherently linked to computer security. Spam propagation through viruses that exploit personal computers is a new challenge, which will require suitably adapted measures. Finally, satisfaction was expressed for the degree of cooperation between the enforcement authorities, which work together in a Contact network set up by the Commission earlier this year.