Women's Pro Tennis

Women's professional tennis began in 1947 with a short-lived series of exhibition matches between Pauline Betz and Sarah Palfrey Cooke, both U.S. National Champions. In 1950-51, Bobby Riggs signed Betz and Gussie Moran to play in a pro tour with Jack Kramer and Pancho Segura, with Betz dominating Moran. Althea Gibson turned pro in 1958 and joined with Karol Fageros ("the Golden Goddess") to play one-nighters as the opening act for the Harlem Globetrotters for one season. For the next nine years, there was virtually no women's pro tennis until 1967 when promoter George McCall signed Billie Jean King, Ann Jones, Françoise Durr, and Rosie Casals to join his tour of eight men for two years.^[39] The pro women then played as independents as the Open Era began.

When the pro men's Association of Tennis Professionals (ATP) came into being in 1972, promoter Jack Kramer invited pro women to play at the Pacific Southwest Championships but offered only $7,500 in prize money versus the men's total of $50,000. When Kramer refused to adjust the prize money, Billie Jean King and Rosie Casals urged a boycott but instead a separate women's tournament was established by Gladys Heldman, American publisher of World Tennis magazine, with the sponsorship of Virginia Slims cigarettes. The WT Women's Pro Tour was set up in 1971-72. The new tour offered prize money nearly ten times more than other pro women's tennis events but it also created a great deal of friction with the USLTA which initially would not sanction the tour. After a series of ultimatums and contract disputes, the conflict was resolved with Virginia Slims sponsoring individual events and the USLTA taking over the tour. In 1973, the U.S. Open provided equal prize money to men and women players for the first time. Billie Jean King, the most visible advocate for the women's cause, benefitted greatly under the improved pay regime, earning over $100,000 in 1971 and 1972.^[40] In the famous "Battle of the Sexes" exhibition match against crafty Bobby Riggs in September 1973, King brought even more media attention to tennis, and to women professionals in all walks of life.

The Women's Tennis Association, formed in 1973, is the principal organizing body of women's professional tennis. It organizes the WTA Tour, the worldwide professional tennis tour for women. From 1971-1978, the event was known as the Virginia Slims Championships. When Avon took over as the tour sponsor from 1979 - 1982, the event was known as the Avon Championships. Virginia Slims returned as the tour sponsor in 1983 and the event name reverted to the Virginia Slims Championships. It remained that way until 1994 when Virginia Slims ended their sponsorship of the WTA Tour. In 1995, without a tour sponsor, the event was simply referred to as the WTA Tour Championships. Since then, the tournament has been named after other event sponsors. From 1996 to 2000, it was called the Chase Championships. In 2001, it was the Sanex Championships while in 2002, it was the Home Depot Championships. In 2003 and 2004, the event name was once again the WTA Tour Championships. Since 2005, with Sony Ericsson taking over as tour sponsor, the event has been called the Sony Ericsson Championships.

From 1984 - 1998, the final of the championships was a best-of-five-set match - making it the only tournament on the women's tour to have a best-of-five-set match at any round of the competition. In 1999, the final reverted to being a best-of-three-set match, as had been the case from 1971 - 1983. The WTA Tour Championships are generally considered to be the fifth most prestigious event on the women's tour after the four Grand Slam tournaments.