Using archival, interview, and industry observation data, this chapter examines how the private military and security company (PMSC) industry uses gender as a claim to legitimacy. However, our findings suggest that this growing industry still has areas for improvement before being a positive force for gender mainstreaming. As this industry grew, so did concerns about its handling of gender issues. A series of high-profile scandals has contrasted with international efforts to both protect and involve women in peacekeeping operations. The industry developed its own regulatory organizations and put a number of checks in place to bring PMSC firms into compliance with international norms. These include involving women in peace processes and ensuring gender equality in military and security work. However, the lack of attention to gender in industry guidelines and organizations demonstrates the ongoing gap between aspirations and achievement. As international norms move toward gender mainstreaming, so does the pressure to demonstrate that they can effectively reflect those expectations. While high-level changes have occurred, it is less clear how much substantive and measurable change has occurred within the industry.