Drawing on comparative ethnographic fieldwork conducted in urban Mozambique, United States, and Sierra Leone, the article is broadly concerned with the globalization of temporal logics and how specific ideologies of time and temporality accompany health interventions like those for HIV/AIDS. More specifically, we explore how HIV-positive individuals have been increasingly encouraged to pursue healthier and more fulfilling lives through a set of moral, physical, and social practices called "positive living" since the advent of antiretroviral therapies. We describe how positive living, a feature of HIV/AIDS programs throughout the world, has taken root across varied political, social and economic contexts and how temporal rationalities, which have largely been under-examined in the HIV/AIDS literature, shape communities' responses and interpretations of positive living. Our approach is ethnographic and comparative, with implications for how anthropologists might think about collaboration and its analytical possibilities.