Before you can do agile with a team, you need a team! At XP Day France last week, a colleague and I started talking shop with Yves Hanouille, who re-introduced Tuckman's model of team growth to us. I've been frustrated for a while, trying to figure out how to get us to follow our own rules, and even suggested throwing out all the rules and starting over. Now I think we need to get through Storming before any of these rules have meaning... You can probably find better info online, but these notes will help me remember the key goals of each phase :
Forming: agree on goals/vision as described by leader (team lead is directive at this stage). Members hold back their own opinions in order to be polite, they mostly work independently on tasks.
Storming: (directive leader) there's a lot of competition for ideas, the team begins to select a leadership model, and roles are clarified
Norming: (collaborative leader) members compensate for each other, agree on rules/standards, and hold each other accountable
Performing: (collaborative leader) interdependent individuals with established conflict resolution mechanisms.
A group in N or P will fall back to S under stress, in which case the team lead will need to be directive again.
So I think a team needs to be at either N or P to do agile. It's possible that at F or S the directive leader of the group will impose an agile process... but it won't be self-organizing!