President Franklin D. Roosevelt and Undersecretary of State Sumner Welles began trying to make military matériel available to Latin America during the latter 1930s. Little progress was made until passage of the Lend-Lease Act in 1941 enabled Washington to furnish eighteen Latin American nations with about $493,000,000 worth of military assistance during World War II. This study, based primarily on State Department lend-lease decimal files in the National Archives and documents published in Foreign Relations volumes, views the policy's background, development, and implementation in each recipient nation. The conclusion is that the policy produced mixed results for the United States and Latin America.