The authors describe how law enforcement agencies can use barrier analysis, a method of assessment aimed at identifying potential obstacles to obtaining resources or participating in a program, to better understand and address the challenge of creating diversity among their personnel. They examine key points in the career lifecycle, such as recruitment, hiring, promotion, and retention practices, to determine where women and racial/ethnic minorities face obstacles that might account for less-than-proportionate representation among applicants, hires, and senior leadership. They describe the barrier analysis process, illustrate how it can help law enforcement agencies increase the diversity of their workforce, and present case studies featuring police departments that have used barrier analysis.