Utilizing mixed methods, we examined intimate partner violence (IPV) behaviors among 428 female sex workers (FSWs) who use drugs and their noncommercial male partners in Tijuana and Ciudad Juarez, Mexico. Half of all participants reported perpetrating and experiencing at least one type of IPV behavior in the past year. In interviews, drug use emerged as an important theme associated with IPV behaviors, and we found men and women differed in their motivations for engaging in IPV behaviors. Findings highlight how gender and power are interlinked with and may exacerbate drug use and IPV behaviors among marginalized populations.