The paper outlines the institutional development of UNMIK and its evolving models of cooperation with provisional Kosovo bodies of governance. It provides a brief description of UNMIK’s mandate, contained in UN Security Council Resolution 1244 of 10 June 1999, and the internal structure the international civilian presence has adopted on the ground. This structure, which, under the overall leadership of the SRSG, divides responsibilities among several international organisations, i.e. the UN itself, UNHCR, the OSCE, and the EU, has become known as the “four pillars”. As this paper mainly focuses on the factual-historical aspects of institution-building in Kosovo under UNMIK’s administration, the aspects of analysis and qualitative evaluation are kept rather on the margins. However, the purpose of the paper is to provide an independent and objective background for analytical observations to be made.