Forming, storming, norming and performing are the four key stages in team formation.
Forming: This is a short lived period when the team initially gets together. The members get to know each other and why the team has been formed. The team leader is strongly in control at this point.
Storming: At this stage team members frustration will surface, perhaps wanting to get on with the work or not wanting to be on the team or not agreeing with the direction it is taking. Others may be excited about the team and be hard to focus. The leaders role is challenged at this stage. This can often be the end of the team before it really gets started.
Norming: At this stage the members know each other and roles have been established and the aims of the team determined and work is underway.
Performing: Progress is being made toward the goal, the team is supporting each other and the leader is delegating work easily.
It is worth remembering these stages when you bring a team together so that when you are frustrated about its members or progress you can consider what stage it is in and facilitate it toward the next.