A sexual double standard (SDS) is the application of different standards to the sexual behaviors of different groups or individuals, most often women and men. Sexual double standards (SDSs) take many forms, varying in the individuals and sexual behaviors being evaluated, the context of these behaviors, and the types of evaluations being made. Research findings about SDSs depend on who is studied, how SDSs are defined, and how acceptance of SDSs is measured. Acceptance of SDSs varies over time and across countries and subcultures.