The study in this week’s issue of PLOS Medicine by Jewkes and colleagues on the prevalence of consensual male-male sexual activity and non-consensual male-on-male sexual violence, and their respective associations with HIV infection in South Africa [1], makes an important contribution to the dearth of literature on population-based HIV prevalence amongst men who have sex with men (MSM) in the African context. The paper highlights several important findings, including that HIV prevalence amongst South African MSM also has public health implications for South African women, given high levels of bisexuality and sexual concurrency amongst South African MSM. Assuming these findings are generalizable to the rest of sub-Saharan Africa, addressing the health needs of African MSM will require policymakers to meaningfully address significant socio-cultural and legal barriers that hinder access by MSM to HIVrelated health services. Failing to do so will fuel the spread of HIV in African men who engage in consensual male-male sexual activity and/or who are victims of male-on-male sexual violence. Socio-Cultural Barriers