This article explores the development of international relations (IR) in Indonesia with special focus on the changing trends in its theoretical perspectives. It argues that the academic works examined reflect the ways in which Indonesia's IR scholars perceive and theorize the nature of the dynamics of external political environments and their connections to the state's foreign relations. The argument is elaborated in two related parts. The first section discusses the theoretical perspectives that developed during the Cold War period, which focuses on the propensity toward historical realism and regionalism. The second part of the discussion examines recent developments in which Cold War perspectives have been reconsidered, and in many respects modified into three new categories of theoretical thinking, namely reform, resistance, and eclecticism. The changing theoretical trends reveal that Indonesia's IR scholarship is open and innovative. The conclusion comments on the development of the Indonesia's IR.