Explaining policy change is one of the most central tasks of contemporary policy analysis. Reacting to overly rigid institutionalist frameworks that emphasize stability rather than change, a growing number of scholars have formulated new theoretical models to shed light on policy change. Focusing on health care reform but drawing on the broader social science literature on policy and politics, this article offers critical perspectives on the institutionalist and ideational literatures on policy change while assessing their relevance for analyzing change in contemporary health care systems. The last section sketches a research agenda for studying policy change in health care