To those well versed in therapy-speak and the self-help world, the name John Gray can provoke some eye-rolling and sarcasm: Men are from Mars, women are from Venus. Yeah, yeah, yeah. We genders need to "learn" to "communicate."

What's remarkable is Gray's role in making this concept so well known. In 1992, when Men Are from Mars, Women Are from Venus was published, the idea was anything but pedestrian. Indeed, Gray sparked both revolution and debate in the world of gender politics.

His case is simple: "Men mistakenly expect women to think, communicate, and react the way men do; women mistakenly expect men to feel, communicate, and respond the way women do. We have forgotten that men and women are supposed to be different. As a result our relationships are filled with unnecessary friction and conflict," he wrote in the first chapter of Men Are from Mars. Though the idea is not radical, the implication met with criticism from feminists who said that it tried to reinforce stereotypes; and with accolades from stricken couples who found that Gray did, in fact, help them communicate and understand each other better.

Though naysayers have called into question both Gray's message and his credentials, his appeal is undeniable. Word-of-mouth has proved strong enough to drive sales of Gray's book and its companions -- targeted at everyone from dating singles to coworkers -- into bestsellerdom, with the first title alone selling more than 15 million copies. He has also become a cottage industry of gender relations, with seminars, media appearances, and audio titles bolstering his books.

Gray's style tends to be simple and direct, with analogies along the lines of the title: "Men Are like Blowtorches, Women Are like Ovens" and "Men Pursue and Women Flirt" are typical chapter headers. For those mired in the tricky morass of dealing with the opposite sex, the author's no-nonsense approach is appealing.

In 1999, Gray departed from his relationships milieu to the broader palette of life fulfillment with the parenting guide Children Are from Heaven and How to Get What You Want and Want What You Have, a guide to achieving success while bolstering one's spiritual life via meditation and awareness of worldly challenges. It's a strong statement coming from someone who lived for several years as a monk, but Gray's strong suit with readers remains his relationship tomes. Since the original Mars/Venus title, he has created a franchise that now straddles the realms of love and personal success. His advice obviously rings true with millions of readers.