The key issue of social life is the problem of solidarity. This problem, as the recent events show, will grow more acute in the near future, both in Russia and around the world, which is especially evident in the crisis. The paper will consider the question of solidarity in the context of the theory of sociology. As the outcome of this investigation the increase both in the knowledge of social life and in the theoretical resources for its study is expected to be. Thus, the research is considered to become, first of all, the contribution to the theory of sociology, but not formal sociology ­— rather pithy one, oriented towards the current issues’ resolving.