The problem of the conservation of the ethnic culture of small groups in conditions of the absorbing influence of a socioculturel enclave is formalized. Different methods for preventing assimilation are considered. Based on the solution of simplified equations, the relation between the action and the effect achieved is found. The algorithm of the harmonization of interests of the group and its potentialities is described. The principle of intergroup concordance expressing the compromising of ethnic cultural interests of groups is formulated. Numerical examples are presented.