The theory of entrepreneurship is currently one of the most advanced sections of economic science. This theory is still developing and expanding. One of the new trends in modern business theory, widely discussed in the international economic science, is the study of the social entrepreneurship phenomenon. Study findings on social entrepreneurship have also been published by Russian economists. Although social entrepreneurship has been studied for more than thirty years now, the totality of the results obtained cannot be viewed as social entrepreneurship theory. The notions about this interesting phenomenon are presented in an eclectic form and have yet to be systematized. Moreover, while some researchers say that it is a new paradigm in business, others argue that it has been observed for several centuries. As shown in the article based on the analysis of major published works, there is still no consensus among scientists as to what constitutes social entrepreneurship. It is shown that attempts to define this concept have proved unsuccessful. It is not clear from scientific publications how to combine the desire for profit inherent for an entrepreneur with the altruism characteristic of social business. The article proposes to consider social entrepreneurship not as an isolated phenomenon, but as occurring at a certain stage in the life cycle of the entrepreneur when this cycle comes to a bifurcation point. Social entrepreneurship acts as one of the attractors of the further development of the business cycle. As a result of this approach it is possible to explain the conditions required for social entrepreneurship to emerge, to understand the phenomenon of entrepreneurship in the social sphere and to identify the factors that contribute to the development of social entrepreneurship.