Informed by over 150 surveys and 14 interviews with military personnel, NATO elites, and force generators, this book provides a necessary challenge to the policies, processes, and assumptions that are often taken for granted in military organizational cultures of NATO and its member states. NATO's buy-in to gender-sensitive policies and programming at the policy level was only formalized in 2007 with the NATO/EAPC Policy for the Implementation of the Women, Peace, and Security Agenda. The policy reiterates the importance of women's participation across NATO, its member states and partners in order to enhance operational effectiveness. Determining what factors influence women's deployment and participation in the military is essential to meet NATO' and member states' ongoing commitments to gender equality and gender mainstreaming. This book exposes hidden resistances that hinder women's deployment on NATO operations through critical appraisal of NATO's gender architecture and policies, and comparing the perspectives of force generators and policy makers with the experiences of military personnel.