A Working Group is a group of people that are working toward one particular set of goals. Joomla! currently has 7 Working Groups: Translation, Quality & Testing, Development, Documentation, Sites & Infrastructure, Design & Web Standards, and Foundation. Each working group has a specific set of goals, tasks, and responsibilities. Each Working Group has at least one Coordinator that is a member of the Joomla! Core Team. The management and administration of each Working Group is the primary responsibility of the Working Group’s Coordinator and because of that, the Coordinator is free to setup and run the Working Group in any way they see fit and that agrees with our Code of Conduct. This allows for highly agile teams that can each decide which protocols, processes, communication methods, etc. are best for them. You can find out more information about the Joomla! Working Groups by visiting this page: http://dev.joomla.org/content/view/13/53/ (Note: it is a bit out of date).