The paper examines human agency in the production and transformation of global security assemblages. A situated conception of human agency is elaborated theoretically through the reincorporation of key concepts from Gilles Deleuze and Felix Guattari’s original oeuvre, such as ‘bodies’ ‘desire’ and ‘affect’. Through this Deleuzoguattarian assemblage framework it becomes possible to distinguish between human/non-human and active/reactive forms of agency, while not losing sight of how human actions invariably take place within broader structures of signification. To showcase the utility and analytical potential of this approach, the paper returns to a paradigmatic case of global security cooperation in recent times: the military intervention in Libya of 2011. Through the assemblage framework advocated it is illustrated how the agency of the governments of the United Kingdom, France and the United States is crucial for making connections with other bodies in the production of a Libyan humanitarian intervention assemblage, and later bringing about its transformation into a Libyan regime change assemblage. More than this, it becomes possible to grasp how in fact both these processes form part of a single Western-led biopolitical-geopolitical strategy. The paper concludes by emphasising the political and ethical significance of an appreciation of human agency in global security assemblages. De l’intervention humanitaire au renversement du régime en Libye : l’agentivité humaine dans la production et la transformation des agencements de la sécurité mondiale