The small group as object of research takes a special place in system of social sciences. It concentrates in herself a number of important problems as social and practical, administrative, and teoretiko-research character.
Informal type of groups are groups of friends, companions, friends. It is considered standard that optimum performance of groups requires compliance its external (official) and internal (informal) the organizations. How many the relations in official groups, the interpersonal relations would not be formalized, group of members are carried out on signs of sympathies — antipathies.
The hierarchy of real contact groups can be presented as follows: diffusion group — in it relationship is mediated not by the content of group activity, but only sympathies — antipathies; association — group in which relationship is mediated by only personally significant purposes; corporation — relationship is mediated by the content of group activity, personally significant, but asocial on the installations; collective — relationship is mediated by personally significant and socially valuable content of group activity.