Despite the enormous amount of literature which already exists on the Bosnian war, little research has been carried out on the way humanitarian access was negotiated with the warring parties.1 This study, which forms part of a larger research project on the subject of humanitarian access, provides a critical analysis of the efforts made by UNHCR and other international actors to negotiate humanitarian access in Bosnia.2 It looks at the various partnerships and alliances which evolved between these different actors, and their impact on the negotiating process. It covers the period from the early summer of 1992, when the war in Bosnia began, to December 1995 when the war ended with the signing of the Dayton Peace Agreement. Much of the study deals with negotiations between UNHCR and the Bosnian Serb authorities. This is because of the particular difficulties which UNHCR experienced throughout the war in obtaining authorisation for humanitarian convoys to transit through Bosnian Serb territory to the government-held enclaves. The study is based on UNHCR internal documents and reports, as well as interviews with UNHCR officials, staff from other humanitarian organisations and local officials. It draws heavily on the personal experience of the author who, as Head of the UNHCR office in Sarajevo for much of the war, was directly involved in negotiating with the Bosnian government and Bosnian Serb authorities.