As the AIDS epidemic continues to spread across Africa, a demand for evidence produced by policy-relevant research means that expatriate-led research projects have become a fixture in highly infected countries. While many have drawn attention to the social and economic consequences of AIDS suffering, few have documented the everyday practices, contradictions and politics of producing AIDS-related knowledge in impoverished contexts. This study examines the ways in which AIDS survey research projects in Malawi produce new socialities and mobilities, generate new exclusions and inclusions and reconfigure expertise and evaluations of knowledge. Rather than focusing on a single knowledge community, the study follows AIDS knowledge itself as it is formulated and circulates through sites of production (the “field”), conversion and manipulation (the office) and consumption (conferences, journal articles or other forums). Drawing on twenty months of ethnographic fieldwork in 2005 and 2007-08 with case study research projects, researchers, fieldworkers, rural research participants and policy makers in Malawi, this study examines how actors’ positioning within the social field of “AIDS research” informs their stakes in research and analyzes the tactics they employ to achieve them. Central to the study is an illustration of how boundaries and differences (between people, knowledge and context) are produced and negotiated within interactions between actors with multiple and crisscrossing commitments, interests and ideas.