This chapter deals with relations between the colonial medical service and major British missions in early colonial Malawi (c. 1891–1940). It focuses on the networks that connected missions with the medical service and co-operation between the two in information sharing, public health campaigns and the medical training of African staff. Then, the chapter analyses conflicts between missionaries and the colonial state, contests over authority and critiques of policy and practice. Co-operation between the British missions and the colonial medical service in Malawi was extensive and mutually beneficial, but there were also important areas of conflict and contestation. These clashes were kept mostly private, as both sides attempted to present a united front as medical collaborators. However, Western medicine in colonial Malawi was not monolithic or marked by simple dualism between state and missions. Medical practice, practitioners, knowledge and materials were constituted, transferred and connected in complex imperial networks that included Medical Officers, missionary physicians and various medical middles.