During the last decade, the concept of assemblage has become increasingly popular in the social sciences. Originating in the philosophical work of Gilles Deleuze and Félix Guattari, the concept aims to describe the world as a collection of unstable wholes – consisting of discourses, practices and material elements – that lack a universal organizing principle. The aim of this paper is to introduce the concept of assemblage in a Swedish political science context and to show its analytical potential. The historical background of the concept and how it has been translated into analytical strategies in current social science research is described. The paper argues that the concept of assemblage is particularly fruitful for studying the practical work required to put together policies, projects and reforms in concrete contexts. In order to illustrate the analytical potential of the concept, the construction and re-organization of the Swedish university hospital “nya Karolinska” is used as an empirical example. It is argued that the construction and re-organization of “nya Karolinska” was made possible through the laborious work of assembling a multitude of heterogeneous components and practices: standardized care models, private consulting expertise, material objects and knowledge production. In this way, it is shown that the construction and re-organization of “nya Karolinska” cannot be traced to a specific organizing principle, which is a central aspect of the anti-essentialist ontology of the concept of assemblage. The article concludes with a discussion on how the concept of assemblage can contribute to a vitalization of political analysis. Here, it is emphasized how the concept can be used as an analytical tool to make visible complex processes of composition and assembling that go beyond established hierarchies and dichotomies, and as a tool for analyzing how these processes always contain political elements of order and conflict.