An adult theater is a movie theater where pornographic films are shown to an adult audience. For the patrons, rules are generally less strict regarding partial- or full-nudity and public masturbation or sex, and such behavior may be condoned explicitly or otherwise by the management. Such behavior may also be overlooked by local law enforcement. blank">Lap Victory. How a DA's decision to drop prostitution charges against lap dancers will change the sexual culture of S.F. -- and, perhaps, the country. _SF Weekly, 8 September 2004 Certain theaters may also include a strip- or sex-show between films, or other sex industry services.

Most commonly, an adult movie theater shows heterosexual pornographic films but attracts straight, bi and gay male patrons, most of whom are not there for the film but are instead looking for casual and anonymous sex with other patrons. Although women do go to adult theaters, their presence remains a rare occurrence. The over-whelming majority (in many theaters, that can be upwards of 99%) of theater-goers are male.

Before the VCR and, later, the Internet, a movie theater or cinema house was often the only location where the average person could see a hardcore adult film. The two primary activities within any adult theater have always been to view a pornographic film and to engage in sex with other movie-goers whether in the seats, balcony, aisles, behind the screen or in the men's rooms.

As a protection against prostitution being plied on premises, most adult movie theaters do not permit women to enter if unaccompanied by a man. Women are usually allowed to enter only with a male escort.