It's hard to believe that anybody in his right mind would want to be a voyeur.

Voyeurism — defined as "obtaining sexual gratification from observing unsuspecting individuals who are partly undressed, naked, or engaged in sexual acts" — is largely considered sordid and scandalous. Nobody loves a peeping Tom.

But getting your kicks watching someone who doesn't know you're watching her — or him — turns out to be more common than you might think. With reality TV and Internet peep shows all the rage, voyeurism has taken on a whole new definition, and people-watching has become an art of sorts beyond the sexual.

Sexual voyeurism is generally viewed as any of three categories — pathological (clinical), criminal, or a fun sexual pastime (particularly if it’s consensual). Most of the research done on voyeurism has focused on cases where therapeutic or legal issues were involved.

It's the legal, or rather, illegal cases, that capture the headlines and attention of the public (such as the recent case involving ESPN's Erin Andrews), and they're the easiest to study.

But these cases actually tell us very little about voyeuristic tendencies among the rest of the population.

Voyeurism may be seen as an "atypical sexual behavior," but it doesn't always have to cross the line or involve sexual perversity like criminal exhibitionism or frotteurism (rubbing against another for sexual gratification without consent).

In fact, academic literature on voyeurism suggests that most people who engage in this behavior are unlikely to be arrested.

Often, the only times a voyeur gets into trouble with the law are for trespassing or indecency and not viewing per se. Those studying voyeurism over the years have speculated that it’s the risk of getting caught that makes for greater sexual arousal than the appeal of watching people.

For others, their willingness to engage in voyeurism may be dependent on sexual opportunities, or a lack of sexual opportunities.

An examination of police records of voyeurism complaints in Copenhagen revealed that fewer cases of voyeurism were reported after legal restrictions on sexually explicit materials were relaxed in the city. This indicated that secretive voyeurism was likely replaced by more acceptable, legal means of watching others, like X-rated films.

Still, others are simply turned on by watching others naked or engaging in sex acts, with or without their permission.

One study in "Deviant Behavior: An Interdisciplinary Journal" involved a group of men who peered into offices and apartments using telescopes from city rooftops, while another group of couples engaged in mutually observing sexual interactions.

Given perceived sexual norms, these activities may seem downright seedy, until you consider that both men and women rate visual cues as important in selecting mates. With evolutionary theory explaining voyeurism as a contributor to reproductive or mating opportunities, especially for males (who are generally known for being more voyeuristic), it suddenly doesn’t seem as wrong.

Researchers at the University of Chicago reported that the majority of their sample of 18 to 44-year-olds enjoyed watching their lovers undress. Can this be said of you?

Others don't mind watching strangers undress as long as there are no repercussions.

Research in the "International Journal of Sexual Health," involving 318 university students, found that more than 83 percent of males and more than 74 percent of females were willing to watch an attractive person disrobe if they would not get caught. Significantly fewer participants (though more men than women) reported being willing to watch two attractive people having sex.

Researchers speculate that watching two people have sex may feel more invasive than watching somebody undress, which makes sense, given most voyeuristic tendencies tend to be fulfilled within the private moments of our intimate sexual relationships. Or maybe we just protect and respect those moments more.

Dr. Yvonne K. Fulbright is a sex educator, relationship expert, columnist and founder of Sexuality Source Inc. She is the author of several books including, "Touch Me There! A Hands-On Guide to Your Orgasmic Hot Spots."

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