This article presents a new model explaining acquired immunodeficiency syndrome (AIDS) transmission dynamics amongst heterosexually active couples. It covers the assumptions made, the variables analysed, the model's sensitivity and the ordinary differential equations and control strategies used. The information was obtained from the Colombian state Statistics Department (DANE) and applied to different simulations in the system (with and without control), using the MAPLE programme code. Simulation results led to concluding that control using condoms was relevant in the model. It was not important if control were applied in women or men, nor was the percentage of sexually-active men and women.