The diagnosis of HIV infection is the point of entry for treatment and prevention services, yet many infected persons in both developed and developing countries remain undiagnosed. To reduce the number of undiagnosed infections, a variety of expanded testing policies have been recommended, including opt-out testing. This testing model assumes that in populations of increased HIV prevalence, voluntary testing should be offered to all patients seen in healthcare settings and performed unless patients specifically decline. While this approach raises ethical issues (...) concerning “voluntariness”, access to care, and stigma, the potential benefits of opt-out testing far outweigh its potential adverse effects. (shrink)