In 1976, Hay wrote a small pamphlet, which came to be called “Heal Your Body”. It contained a list of different bodily ailments and their “probable” metaphysical causes. This pamphlet was enlarged and extended into her book You Can Heal Your Life , published in 1984  As of February 2008, it is still on New York Times best sellers list.
Around the same time she began leading support groups for people living with H.I.V. or AIDS which she called her "Hay Rides". These grew from a few people in her living room to hundreds of men in a large hall in West Hollywood. Her work with AIDS patients drew fame and she was invited to appear on “The Oprah Winfrey Show” and “Donahue” in the same week, in March 1988. “You Can Heal Your Life” immediately landed on the New York Times best-seller list. More than 35 million copies are now in print around the world in over 30 languages.  and has been made into a movie.
Louise Hay established Hay House Publishing. It is the primary publisher of books and audio books by Deepak Chopra and Doreen Virtue, as well as many books by Wayne Dyer. In addition to running her publishing company, Hay runs a charitable organization called 'Hay Foundation', which she founded in 1985.