The Bracero Program began in 1942 as a temporary wartime measure but was extended repeatedly until 1964. During that time, more than 4.5 million braceros received contracts to work in the United States, primarily as agricultural laborers. Before the program ended, braceros worked in thirty-eight states in the United States, with the majority contracted by eight states. With the attack on Pearl Harbor by Japanese forces on December 7, 1941 and the subsequent sinking of two Mexican vessels by German submarines, Mexico and the United States entered into a bilateral agreement. In actuality, there were two bilateral agreements, the first extending from 1942 to 1949, and the second, enacted as Public Law 78, starting in 1951 and culminating in 1964. Throughout the program’s existence Mexico strove to ensure favorable conditions under which braceros were to be contracted, especially in light of the strong opposition to the program among a number of sectors in Mexico and the long history of discrimination against people of Mexican descent in the United States. Like Mexico, the United States faced opposition to the contract labor program from both employers and labor unions. Employers were wary of too much government interference in their ability to secure a plentiful and cheap labor supply, while labor unions viewed the program as a threat to organizing efforts and as an obstacle to achieving better working conditions and pay for agricultural workers in the United States. The Bracero Program also deeply affected the braceros themselves in both positive and negative ways. And it had a profound impact on the families of the braceros who left to work in the United States. The program was plagued by a number of issues and problems, primarily resulting from a lack of enforcement and widespread contract violations. Despite the problems associated with the program, both countries touted its benefits, not only to their economy, but to the braceros themselves. The braceros did not passively accept their fate and challenged their treatment in a variety of ways. Although the Bracero Program ended in 1964, its legacy continues to affect US–Mexican relations to this day. Furthermore, former braceros and their descendants have undertaken a movement to demand reimbursement for wages promised them under the requirements of the Bracero Program.