The Chaos communicate Congress is an annual meeting of the international hacker scene, organized by the Chaos Computer Club. The congress features a variety of lectures and workshops on technical and political issues.
The event takes place regularly at the end of the year since 1984, with the current date and duration (December 27-30) established in 2005. The congress started out in 1984 in Hamburg, moved to Berlin in 1998, and back to Hamburg in 2012. Having exceeded the capacity of the Berlin venue with more than 4000 attendees, the 2012 meeting in the considerably larger venue in Hamburg set a new record attendance of slightly over 6,000 participants.
A large range of speakers are part of the scene. Organizational work is done by volunteers called Chaos Angels. The non-members entry fee for four days has been 80 Euros since 2006.
An important part of the Congress are the assemblies, semi-open spaces with clusters of tables and internet connections for groups and individuals to collaborate and socialize in projects, workshops, and hands-on talks. These assembly spaces, introduced at the 2012 meeting, combine the hack center project space and distributed group spaces of former years.