We need to teach our sons not only that sexual harassment and assault are never excusable, but also that it is their responsibility to step up and call out their peers when they act or speak in sexist ways. We need to understand and teach our children that sexism, sexual harassment, and sexual assault are all related to each other and on a continuum. Unchallenged sexism creates the permission structure for sexual harassment, which in turn creates fertile ground for sexual abuse and assault.