In 1969, he began a nine-year association with Maharishi Mahesh Yogi before beginning his career as an author and personal relationship counselor.

[1] He received a bachelor's and master's degree in the Science of Creative Intelligence, though sources vary on whether these degrees were received from either the non-accredited Maharishi European Research University (MERU) in Switzerland or the accredited Maharishi International University in Fairfield, Iowa.

[2][3][4] Gray received an unaccredited PhD in 1982 from Columbia Pacific University (CPU), a now-defunct correspondence institution.

[2][5][8][9] In 1992, Gray published Men Are from Mars, Women Are from Venus, which has sold more than 15 million copies[8][10] and, according to a CNN report, it was the "highest ranked work of non-fiction" of the 1990s.

Dorothy Cantor, a former president of the American Psychological Association, has questioned the ethics of creating a franchise for what is essentially a therapeutic process.

El-Batrawi settled with the SEC and was barred from acting as an officer or director of a public company for a period of five years.

[15] Gray is also an early investor in YayYo, Inc, a rental car business for the ride-sharing industry operated by Ramy El-Batrawi.

[22] Gray was accused of borrowing from the work of author Deborah Tannen and he acknowledges some similarities but says, "I was teaching those ideas before I'd heard of her" and that he did not read her book.

[2][30][5] His youngest daughter Lauren markets the Mars Venus brand through her own videos on self-help relationship advice.