Sirojuddin ArifPhilips J. VermonteFenis, Magello Rainer2023-11-212023-11-2120232023-07-21https://hdl.handle.net/20.500.14576/140This research paper examines the impact of the tactics and strategies employed by the Philippine and Indonesian communist movements on political sustainability in the face of repression and a changing political landscape. Utilizing a qualitative approach with causal inference, the research examines the experiences of the Communist Party of the Philippines (CPP) and the Partai Komunis Indonesia (PKI) during their peak periods under authoritarian governments. The PKI operated as a legal party under the Sukarno regime, primarily adhering to Leninist principles. In contrast, the CPP, a Maoist organization, has operated underground since its split from the older revisionist communist party. While existing literature offers valuable insights, a comparative study between these regional revolutionary movements is necessary to bridge the gap in understanding the relationship between party methods and sustainability. Despite encountering state repression, the effectiveness of revolutionary strategies played a pivotal role in determining their survival and future trajectory. Drawing on historical institutionalism theory, the study explores the timing and sequence of events, shedding light on ideological, political, and organizational transformations. Ultimately, the distinctive responses of the CPP and the PKI to the domestic challenges of the Cold War era shaped their respective trajectories in pursuing communist aspirations. The findings of this study will contribute to a deeper understanding of how revolutionary social movements respond to repression in the Southeast Asian region.enAll Rights ReservedCommunist Party of the PhilippinesPartai Komunis IndonesiaSocial movementsMaoismLeninismThesis