In the 1970s, communities of the Kalinga sub-ethnic group in the Cordillera Mountains in northern Philippines successfully halted the construction of a series of hydroelectric dams along their main waterway, the Chico River, which would have caused their displacement. Based on interviews and archival research, the article examines the role played by a Kalinga political institution known as the bodong or peace pact in the Kalingas’ mobilisation against the dam project, using an analytical framework drawn from Charles Tilly's and Sidney Tarrow's work on contentious politics.