This chapter is about Lyndon Johnson’s relationship with Mexican Americans and his work in the arena of US–Latin American relations. Johnson always credited his teaching experience at the “Mexican school” in Cotulla, Texas with his lifelong sympathy toward Mexican Americans, and as the influence that made him want to help them when he was president. But Johnson’s presidency also coincided with a period of great flux for Latinos in the United States and US–Latin American relations more broadly. The number of Latinos in the United States was growing, in part because of the Immigration and Nationality Act that Johnson signed into law in 1965, and in part because the United States needed Cold War allies, so Johnson maintained the “Good Neighbor” policies of his predecessors in order to secure support from Mexico and other Latin American nations. Throughout the civil rights era and the middle period of the Cold War, when Johnson was in office, Latinos were key deciders of their own fate, waging campaigns for greater rights and inclusion in the social, political, and economic life of the United States.