This article examines the recruitment and training of Africans as sanitary inspectors during the British colonial administration of Lagos. The role of these indigenous health workers in shaping the colonial health system shows that colonial hygiene, an essential part of the European “civilizing mission” in Africa, was more than an imperial project in which British colonial health officials led “ignorant” Africans to sanitary enlightenment. Faced with the problem of preventable diseases, rapid and mismanaged urbanization, poor funding of sanitary services, and deteriorating public health conditions, African health inspectors, known locally as wole-wole (house searchers), served as sanitation infrastructure. The non-medical health workers supported the British colonial efforts to improve public health in Lagos by bridging the cultural gap between European medical officials and the African public. Indeed, African sanitary inspectors aided European colonial officials in extending their “civilizing mission,” sometimes using their office to pursue their own interests and breaching the privacy of the local population. Yet, working as intermediaries between the colonial government and Africans, the local sanitary inspectors improved the colonial state’s ability to effect positive social change and relatively deal with preventable diseases in Lagos. The contributions of these Africans, especially Dr. Isaac Ladipo Oluwole, reveal the ability of indigenous people to take care of their health and their active role in colonial state-building.