Sexual fantasy refers to the mental image of a person, object, or situation, often but certainly not always involving a sexual component. Human sexuality is a dimension of social life that is often rich with many different sorts of fantasies. Sexual fantasies often entail mental scenarios involving persons other than one's regular partner and include sexual activities considered culturally inappropriate or unacceptable.

What Triggers Sexual Fantasies?
People vary considerably in their ability to fantasize and in their enjoyment of this behavior. Fantasies may supplant reality for some or may serve as a poor substitute of sexual reality for others. Fantasies are often triggered by external stimuli, such as an attractive stranger or an erotic picture, movie, or story.

Researchers have varying views on gender differences in fantasizing. Some argue that males are more prone to fantasize while others assert that fantasy is more common among women. Linda Wolfe studied a sample of 15,000 women ages 18-34, and less than three percent said they never fantasize.

Male Sexual Fantasies
In Western societies, males more often use sexually explicit material as a part of fantasy, whereas females are more likely to rely upon romance stories. Females are more likely to prefer erotica with a "softer," more imaginative side rather than the "harder," more explicit forms preferred by many males.

The male fantasy world relies heavily upon novel experiences filled with culturally-defined beautiful women who are always sexually available and free. Pornographic magazines such as Playboy and Penthouse, as well as a wide array of so-called harder publications (because they depict explicit sex acts), attempt to capitalize upon such fantasies.

Female Sexual Fantasies
Women often base their fantasies upon previous sexual experiences and tend to emphasize romance and intimacy. The onset of the women's liberation movement has created a renaissance in erotic fiction aimed at women by women writers and film makers.