Rescates (ransoms) consisted of the repurchase by Spanish and Spanish American merchants of ships and cargoes taken as prizes during wartime and sold in the British West Indies. This is the first detailed study of the subject, drawing on archives in Britain, Spain and the Americas. It is argued that rescates typified a broader range of legal ruses designed to protect Anglo-Spanish trade in the Americas from both wartime disruption and customs interference. As a mechanism for the legal protection of commerce promoted by both the British and the Spaniards, rescates enjoyed considerable success during the war that commenced in 1796, especially with respect to trade between the British ports in the Caribbean, Cuba and Mexico. They thus played a key role in the strong and sustained growth which characterised trade between the British and Spanish empires during these years.