The literature on participatory practices in organizations has been less coherent and more limited to subspecialties than the literature on bureaucracy in organizations -despite a number of celebrated studies of participation in 20th century American sociology. Due to the practical nature of participatory reforms and the ambiguity of participation as a concept, attempts to review participatory knowledge have a tendency to focus on refining definitions and clarifying frameworks within subfields. This article instead provides a broad thematic overview of three different types of research on participation in organizations, all critical to an understanding of today's dramatic expansion of participatory practices across a variety of organizations. Classic research studied participation as dynamic and central to organizational legitimacy. Institutional design research has focused on participation as a stand-alone governance reform with promising empowerment potential, but mixed results in domains such as health care, environmental politics, and urban planning. Finally, recent research seeks to place participatory practices in the context of shifting relationships between authority, voice, and inequality in the contemporary era. The article concludes with suggestions for building on all three categories of research by exploring what is old and new in the 21st century's changing participatory landscape.