Abstract
This article investigates how a medical non-governmental organisation Médecins sans frontières (MSF) developed and promoted the treatment of Hepatitis C (HCV) in Cambodia. This article is based on an operational archive collected in real time within the MSF mission which was completed with repeated oral history interviews over a period of 5 years across the history of the humanitarian 'mission' between 2016 and 2021. This archive and a historical account produced synchronously revealed the evolution of the role of humanitarian organisations in setting the medical agenda regarding the development of a nation's health priorities. The article argues that such a campaign represents a new development for the history of humanitarian medicine. As an experimental historical project, we aimed to capture how a humanitarian organisation defined its intervention as a 'proof of concept' and developed a public health campaign from a vertical approach reliant on new and very effective treatments.