Zanjeras are resource management institutions that have endured for centuries in the Ilocos region of northern Luzon. By most accounts, these cooperative irrigation societies emerged during the Spanish regime when Augustinians were deployed to congregate indigenous populations into pueblos, convert them to Christianity, and raise tributes for the Crown. The book explores these challenges and proposes actions that governmental bodies can undertake to strengthen the adaptive capacity of zanjeras and other irrigation communities around the world.