Organizing scholarship both chronologically and thematically, this article provides a review and critical evaluation of the literature that examines factors influencing criminalization. The first part of the paper examines three streams of inquiry and theorizing: (a) classic work that has shaped decades of scholarship on criminalization by focusing on the relationship between demographic changes, material and symbolic politics, and the emergence of criminal law; (b) contemporary work that unpacks the nature of the relationship between organizational, social movement, and state-related factors that structure and mediate the outcome of definitional and political processes involved in efforts to criminalize elements of social life; and (c) more recent work that envisions criminalization as a social process intimately connected to, and indeed arguably derivative of, larger processes of institutionalization, globalization, and modernization. The discussion and conclusion section summarizes the consequences of these three streams of inquiry and theorizing for our collective understanding of the structures and processes that underlie criminalization. Thereafter, the article concludes with a proposed agenda for subsequent research on criminalization and related topics.