Frotteurism involves unsuspecting or nonconsenting partners; the sexual fantasy or arousal focuses on surreptitious touching or rubbing. Typically, the man may touch or fondle erogenous zones of the target female such as buttocks, breasts, thighs, or genitalia. Other men rub their penis, usually with an erection, against the buttocks or crotch of an unsuspecting woman. Males are rarely targets for men with this disorder.

When children are the targets, the diagnosis is usually pedophilia. It is the furtive nature of the contact that is the stimulus for sexual excitement in frotteurism. Touching as an overture to more involved sexual contact is not frotteurism, nor is touching associated with poor judgment, as in mental retardation, deficient social skills, or problems with impulse control.