This thesis tells a unique story of Britain's medical humanitarian response and its politicisation, as the British government attempted to promote its position within a changing international global order. It examines the networks, debates and negotiations that took place between different actors within the British aid sector, and examines their impact on norm-setting and aid delivery. From a sector that is often articulated in terms of human need, this thesis traces the movement of medical humanitarianism into the heart of global politics and its manipulation as a tool of the British state. Literature that champions France, as the primary medical actor, has led to the marginalisation of Britain's medical response within humanitarian narratives. The focus of medical humanitarian aid, throughout this thesis, offers a lens through which the relationships between actors within the British aid sector can be explored. By drawing together the work of modern historians, oral histories and grey literature, this thesis showcases the unique nature of British medical humanitarianism. Through the investigation into the impact, and growth, of medical responses, this thesis eschews the institutionally-dominated narratives of British humanitarianism. Rather, it brings to the forefront the key role of smaller, medically-focused organisations, individual aid practitioners and research bodies, often overlooked in current historiography, and explores how they interacted with the British Government and larger British NGOs. In doing so, this thesis examines the distinctive trajectory of British medical aid at the end of the Cold War and explores the impact of neoliberal ideas and the changing global political arena on the British aid sector. To understand the roles of these many actors, this thesis investigates snapshots of medical humanitarian deployments between the years 1988-2014. Each chapter of this thesis explores a humanitarian response to a different crisis, specifically foregrounding the medical response. Beginning with a study of the Armenian Earthquake in 1988, this thesis explores Britain's role within the first delivery of international aid to the Soviet Union since the beginning of the Cold War. The second chapter then progresses to examine the British response to the Sudan famine in 1998. It grounds this response in the debates that were taking place, within academia, about the nature of humanitarian response. The following two chapters of this thesis then explores New Labour's internationalist agenda and its impact on British medical humanitarian response. Chapter 3 investigates the peak of this, identified during the humanitarian response to the bombing of Kosovo in 1999. Chapter 4 examines the consequences of an over-emphasised internationalist narrative, investigating the British response to the Iraq war and its impact on the heavily militarised medical humanitarian response. Finally, this thesis ends with an examination of the biggest medical humanitarian response ever deployed by Britain, the response to the Ebola outbreak in Sierra Leone in 2014. Certain motifs such as: modes of knowledge production, the role of the military and the changing understandings of medicine, are threaded throughout these chapters to draw together these snapshots and to present a narrative of change. By applying historical methods to a period more often understood through social science lenses and personal narratives, this study extends the existing historiography of British humanitarianism, to demonstrate the shifting relationships, processes, and interactions that influence policy change and shape medical humanitarian deployments.