Based on a qualitative case study of a multiyear, multicity attempt to forge community coalitions against substance abuse, this article analyzes three categories of organizational temporalities: cycles, event streams, and temporal style. Community initiatives based on collaboration, coalitions, and cooperation, projects that "bring everyone to the table," provide an opportunity for naturalistic observation of the unanticipated, but analyzable, effects that emerge when mismatched organizational temporalities interact. This article lays out a theory of these emergent effects of interorganizational time conflicts in communities of organizations. The aim is not to argue for the primacy of temporal effects over other dimensions but to include them in a multidimensional view of the causes of problems encountered in multi-organization community initiatives. Keywords: community; time; organizations; community initiatives "Time" is a common scapegoat when broad-based community social interventions face implementation challenges or produce disappointing outcomes: "too little, too late"; "there are only so many hours in the day"; or "the timing was wrong." These clichés suggest, respectively, that the right program arrived at the wrong moment and did not last long enough, that the right people were doing the right things but not enough to make a difference, or that the effort might have succeeded had it occurred under conditions prevailing at some other point in time. Mindful of such observations, both funders and program designers have become "temporally generous," supporting longer projects, providing resources to ensure that new programs represent net increases in effort, and requiring more planning, timelines, and milestones and documentation of community readiness.Nevertheless, even programs with generous temporal endowments seem to be plagued by time-related problems. Participants complain that organizers waste their time in meetings, project leaders cannot keep on schedule, deadlines are missed. Familiar phenomena such as Parkinson's law-the tendency of work to expand to fill the time available (Parkinson 1957