There are significant ethical, public health, and human rights implications for failing to provide detainees and prisoners with adequate safety and health care, particularly with regard to infectious diseases such as HIV and AIDS. In other words, there is an ethical obligation to earmark resources, even when scarce, toward the study and care of prisoners. At the same time, however, how disease surveillance and treatment are carried out in this population—especially with regard to infectious diseases associated with stigmatized or illegal behaviors—raises a different set of ethical issues: For example, obtaining an accurate picture of disease prevalence and incidence rates in prisons as well as effectively treating prisoners may place prisoners at increased risk of physical and legal harms. Thus, both failing to advocate for the incarcerated as well as advocating in a poorly considered way are cause for concern. Additionally, misleading metaphors surrounding prisons and penal systems and the marginalization of prisoners and certain socioeconomic classes lead to a perpetuation of diseases such as HIV and AIDS throughout societies in general. Brazil provides a telling example in that, despite the fact that it has one of the most innovative and proactive HIV/AIDS programs in the world and its Constitution frames health care as a right of all, its imprisoned populations, like those in other countries, shoulder the double burden of being both from lower socioeconomic classes with limited access to resources and at markedly higher risk of contracting HIV than those in the general population. Appropriate solutions will require political, institutional, and cultural changes that assure equitable access to medical care, avenues for real rehabilitation, and safe environments within and beyond prison walls, as well as actions to reduce legal prohibitions against drug use, destigmatize sexual behaviors, and resolve entrenched social inequities.