The chapter examines the cultural contact between the Waorani indigenous group and Ecuadorian society that occurred between the years 1950 and 1970. The Waorani are a group of 4,000 hunter-gatherers from the Amazon jungle that remained in voluntary isolation until the arrival of missionaries from the Summer Institute of Linguistics (SIL). Historically, the Waorani were represented as the “other”; the savage with a history of attacking neighboring indigenous people and the nascent Ecuadorian oil industry that wanted to exploit indigenous territories with the support of American evangelists. Among the strategies and consequences of evangelization were population movements, a reduction of enemy tribes in a single territory, infections and deaths from diseases, the expansion of the community’s agricultural and economic frontiers (colonization and extractivist industry), and socioeconomic changes. The Waorani responses reflected a sui generis interpretation of the Christian message that attempted to reconcile distinct universes of meaning and significance. The chapter highlights the recorded testimonies of the first Waorani converts and accounts from SIL missionaries.