Labor migration is a new and, as all researchers pay attention to, a little-studied trend in the global process. So far, there is no even a clear definition of the phenomenon. Not only is this concept differently interpreted in different countries, which undoubtedly reflects on the imperfection of statistical accounting, but it does not represent the sociological essence of the phenomenon. The purpose of the publication is to present the main types of definitions, comparing the official, Dutch and Russian approaches, and also, briefly describing the main theories, to show the general trend towards the development of sociological foundations, partially replacing the currently dominant legal and economic ones. The publication methodology is a critical review of existing definitions and theoretical approaches. The result is the substantiation of a new approach to the concept of «labor migration», which implies the consolidation in it of certain and varied responsibilities of the state in relation to registered foreign workers.