The G-spot (or Grafenberg spot) is a dime- to half-dollar sized area of especially high sensitivity, situated beneath the surface of a woman's vagina on the wall toward the front of her body.

While the precise location varies, the G-spot is typically situated about halfway between the pubic bone and the cervix, about three inches into the vagina.

Researchers have found that some women experience sensitivity more generally along the upper vaginal wall, rather than in a definable spot.

Because the G-spot is beneath the surface of the vaginal wall, it must be stimulated indirectly through the vaginal wall. Many women reportedly notice an urge to urinate when the spot is initially stimulated, but find continued stimulation (with an empty bladder) very pleasurable. Some go on to experience orgasm, and some expel a fluid along with the orgasmic contractions.

A Source of Great Debate

Named by researchers Alice Ladas, John Perry and Beverly Whipple in honor of the German gynecologist Ernst Grafenberg, who first wrote about it, the G-spot's existence, as well as its location, has been a source of great debate and controversy. Grafenberg himself identified the sensitive area as the point where the urethra (the tube that carries urine from the bladder) runs closest to the top of the vaginal wall.

Ladas, Perry and Whipple argue that the area is located higher up along the vagina, while Israeli sexologist Dr. Zwi Hoch claims that the entire anterior wall of the vagina, rather than one particular spot, is filled with nerve endings capable of producing intense arousal when stimulated. Other research seems to show that the G-spot does not exist at all for some women.

Since orgasmic function in women is highly individualized — in other words, women vary greatly in how and if they achieve orgasm — whether a woman orgasms with G-spot stimulation and where her G-spot is will vary, says sex and relationships expert Dr. Drew Pinsky. "Recent research is showing very clearly that orgasmic function and the means by which women orgasm is highly genetically based," says Dr. Drew. "Whether a woman has an orgasm exclusively with oral sex and direct clitoral stimulation, or with intercourse and primary stimulation, or through intervaginal mechanisms such as the G-spot is something that is determined by the genes they inherit."

Still, for women who have the potential for orgasm with intercourse as well as with direct clitoral stimulation, stimulating the G-spot can be useful, says Dr. Drew. "But worrying about it's exact location is not particularly fruitful."

As for the idea of a male G-spot, don't bother looking. "There is no male G-spot," says Dr. Drew.