In Mosquito Work, Ann H. Kelly and Javier Lezaun reimagine global health by returning to its most persistent problem: the mosquito. Drawing on nearly two decades of ethnographic and historical research across Africa, Latin America, Europe, and the former Soviet Union, the authors follow entomologists, technicians, community volunteers, and the mosquitoes themselves to illuminate the collaborations, experimental improvisations, and political entanglements that shape contemporary disease control. In each setting, Kelly and Lezaun explore how expertise is crafted, how interventions take shape, and how scientific attention to mosquito life becomes a vehicle for imagining different futures of global health. The painstaking effort to come to grips with the dynamic behaviors, elusive ecology, and irrepressible recalcitrance of mosquitoes offers crucial insight into what global health can know and do. Mosquito Work reveals a world where intervention depends less on silver bullets than on forms of care, persistence, and collaboration that unfold close to the problem at hand.