This research note presents an overview of the contemporary “professional organization” research area. We begin with the historical roots and evolution of research into professionals and the organizations in which they work, identifying five theoretical traditions—namely sociology of organization, sociology of the professions, professional organization, professional service firms, and public professionalism. Reviewing recent research in these areas allows us to identify important research phenomena—such as hybridity, institutional work, internationalization, and professional identity—and to understand how the institutional view within the “sociology of the professions” tradition has become a dominant paradigm for this research. This review also reveals the extent to which various occupations, methodological approaches, and academic fields, and locations have assumed positions of importance in recent years. Finally, future directions relevant to sociology researchers are discussed.