This article explores the collection, compilation and circulation of contested quantitative data within an emerging HIV/AIDS apparatus in Vietnam, a United States–led apparatus that prioritizes indicators of performance, fiscal efficiency, and quantitative measures of program effectiveness. In Vietnam, as in many places, biological and behavioral surveillance data are virtually always incomplete and contestable, even as such data has become an essential driver of funding and programming. Experts in Vietnam have developed tentative systems by which such data are “negotiated” into usable forms. Such data are then deployed in computer models to determine funding allocations and select target populations and interventions based on the best dollar-for-infection-averted projections. This article explores these tentative systems as a means of examining a contemporary health humanitarian apparatus, one that operates on demonstrable neoliberal principles, that I have elsewhere called an “economy of virtue.”