Born Mary Kathlyn Wagner in Hot Wells, Texas, Ash worked for several direct sales companies from the 1930s until the early 1960s, achieving considerable success as a salesperson and trainer. Frustrated, however, at being passed over for promotions in favor of men, she retired in 1963, intending to write a book to assist women in business. The book turned into a business plan for her ideal company, and in September 1963, Ash and her son, Richard Rogers, began Mary Kay Cosmetics with a $5,000 investment. The company originally operated from a storefront in Dallas but grew rapidly, particularly after Ash was interviewed for CBS's 60 Minutes in 1979. The famous pink Cadillacs awarded to top sales people were the most visible sign of the company's success.

Ash was widely respected, if not always understood, for her unconventional approach to business. She considered the Golden Rule the founding principle of Mary Kay Cosmetics, and the company's marketing plan was designed to allow women to advance by helping others to succeed. Unfailingly supportive and enthusiastic, she advocated \"praising people to success,\" and her slogan \"God first, family second, career third\" expressed her insistence that the women in her company keep their lives in balance.

Both during her life and posthumously, Ash received numerous honors from business groups, including the Horatio Alger Award. A long-time fundraiser for charities, she founded the Mary Kay Ash Charitable Foundation to raise money to combat domestic violence and cancers affecting women. Ash served as Mary Kay Cosmetics' Chairman until 1987, when she was named Chairman Emeritus. She remained active in the company until suffering from a stroke in 1996. Richard Rogers was named CEO of Mary Kay Inc. in 2001. At the time of Ash's death, Mary Kay Cosmetics had over 800,000 representatives in 37 countries, with total annual sales over $2 billion at retail.

Mary Kay authored three books, all of which became best-sellers. Her autobiography, Mary Kay, has sold more than one million copies and appears in several languages. Her business philosophy, Mary Kay on People Management, continues to be a great source of wisdom and has been included in business courses at the renowned Harvard Business School. Mary Kay Ash's third book, You Can Have It All, was launched in August 1995 and, remarkably, achieved \"best-seller\" status within days of its introduction. Her speeches and quotes continue to inspire the women of the Mary Kay sales force. Mary Kay suffered from a stroke 5 years before she died. She died November 22, 2001.

Mary Kay Ash is interred in the Sparkman-Hillcrest Memorial Park Cemetery in Dallas, Texas.