This article examines the revival of adat (custom) in post-Suharto Indonesia, a movement which few Indonesia-watchers predicted. Four general reasons for the rise of adat revivalism are identified. The first is the support, both ideological and concrete, of international organizations and networks committed to the rights of indigenous peoples. The second is the uncertainty, together with the opportunities, attendant on the processes of democratization and decentralization which followed the end of Suharto's authoritarian rule. The third is the oppression of marginal population groups under the New Order. The fourth root is historical, having to do with the positive role which adat has played in the country's political imagination since the beginning of Indonesian nationalism. Adat as a political cause involves a set of loosely related ideals which, rightly or wrongly, are associated with the past: authenticity, community, order, and justice. These ideals have been invoked in varying proportions to pursue a wide variety of political ends, including the control of resources and the exclusion of rivals as well as the protection, empowerment, and mobilization of underprivileged groups.