"people tend to want to know something about the other members; have to develop a degree of interdependence in order that the group or team may achieve its tasks and be satisfying to its members; and has to learn at some level to deal with conflict if it is to survive. The most influential model of the developmental process - certainly in terms of its impact upon texts aimed at practitioners - has been that of Bruce W. Tuckman (1965). While there are various differences concerning the number of stages and their names - many have adopted a version of Tuckman's model - forming, storming, norming and performing" http://www.infed.org/thinkers/tuckman.htm