Since the 1970s, gender expertise has achieved a high degree of salience in global governance processes in general, and, over the last decade, within institutions concerned with international peace and security in particular. This study addresses the question of what happens when feminist knowledge is incorporated into the discourse of security institutions. It draws on Michel Foucault's concept of governmentality to examine the contingent encounters of feminist discourses with the liberal peace paradigm and traditional conceptions of security in the context of United Nations multidimensional peacekeeping operations over the period 1999–2010. Throughout these encounters, political rationalities of peacekeeping tend to subjugate feminist objectives to the broader goal of conflict resolution. Simultaneously, feminists and women's rights activists who engage with mainstream peacekeeping rationalities are turning into potentially influential ‘gender experts’, who contest and redefine traditional meanings of p...