The governments of Peru and Ecuador signed an agreement with the Global Fund to Fight AIDS, Tuberculosis, and Malaria to help guarantee comprehensive quality of care to people living with HIV, including access to antiretrovirals (ARVs). Current methods of surveillance are inadequate in estimating the true burden of disease. Broad access to ARVs in countries without regular drug resistance testing can also cause rapid development of ARV resistance. By establishing a more sophisticated surveillance system able to capture HIV incidence, prevalence, patterns of HIV resistance, and genetic variability of viral strains, Peru and Ecuador will be better equipped to monitor the HIV epidemic, develop personalized prevention and control measures, and track patterns of HIV resistance among infected patients. This study will estimate the incidence of HIV, syphilis, and herpes simplex virus 2 (HSV-2) among MSM in Peru and Ecuador, as well as examine the number and variability of ARV-resistant HIV strains.