The monograph reflects the role of social work in the process of professional identification and substantiates the construction of a specific branch of sociological knowledge - professional identity in conditions of mass marginalization of society. Taking into account the specificity of social work with identity, which allows overcoming the marginalization, the author puts and solves the problem of professional identity, interpreting it as a complex phenomenon, social and psychological reality, including different levels of consciousness, as well as individual and collective, ontogenetic and sociogenetic foundations. Setting the problem of professional identity, its genesis and structure, and defining the discourses of its understanding are urgent tasks due to the identity crisis of the modern man. The monograph may be of interest to teachers, postgraduates, and students focused on sociological problems, as well as can be applied in social work practice.