Studies of the causes and consequences of turnover at the group, unit, or organizational level of analysis have proliferated in recent years. Indicative of its importance, turnover rate research spans numerous academic disciplines and their respective journals. This broad interest is fueled by the considerable implications of turnover rates predicting broader measures of organizational effectiveness (productivity, customer outcomes, firm performance) as well as by the related perspective that collective turnover is an important outcome in its own right. The goal of this review is to critically examine and extract meaningful insights from research on the causes and consequences of group, unit, and organizational turnover. The review is organized around five major “considerations,” including (1) measurement and levels of analysis issues, (2) consequences, (3) curvilinear and interaction effects, (4) methodological and conceptual issues, and (5) antecedents. The review concludes with broad directions for future research.