Exercise ALCORA, launched in 1970, was a military understanding negotiated, in secret, by Portugal, Rhodesia, and South Africa. Between October 1970 and April 1974 there were regular meetings of the various ALCORA bodies, which had the effect of bringing closer the staff officers of the three armed forces. The military ties between the three countries were further deepened through the creation of permanent ALCORA planning and intelligence organisations, as well as dedicated military forces. This article examines ALCORA’s trajectory, and the hopes deposited in it by its promoters, as well as its eventual demise in the wake of the Portuguese revolution of 1974. It pays close attention to the links between that trajectory and the changing security situation in southern Africa, notably in the Tete province of Mozambique, the source of mounting concern within the ALCORA establishment. The shortcomings of ALCORA are also highlighted, notably its failure to identify the greatest of all threats: Portugal’s waning commitment to its colonial wars.