Whatever Happened to Critical Mass Theory? A Retrospective and Assessment *

Between 1983 and 1993 the authors published a series of articles and a book promulgating and explicating “Critical Mass Theory,” a theory of public goods provision in groups. In this article we seek to trace the growth, change, or decline of the theory, primarily through an analysis of all journal citations of the theory. We find that the majority of citations are essentially gratuitous or pick a single point from the theory, which may or may not be central to the theory. However, we identify four lines of theorizing that creatively use substantial parts of Critical Mass Theory in their own development: (1) theories relevant to issues in communication studies such as interaction media and shared databases; (2) Macy's work on adaptive learning models; (3) Heckathorn's models of sanctioning systems; and (4) theories that are centrally concerned with issues of influence in collective goods processes. A few additional, less-developed lines of work are also discussed. None of this work identifies itself as being itself “Critical Mass Theory,” but many of the innovations and assertions of the theory are important bases for its development.