She qualified for the Tour in August 1983 and captured her first win at her fifth event, the SAFECO Classic. In 1984, she became the first ever rookie to win two major championships in one season, the Nabisco Dinah Shore after a sudden-death play-off with Pat Bradley and the du Maurier Classic (Se Ri Pak matched this feat in 1998), and was named LPGA Rookie of the Year.
In 2006, the American earned her 31st career win at the Safeway International Presented by Coca-Cola, where she crossed the $10 million mark in career earnings to become only the third player in LPGA history (at the time) to reach that milestone; crossed the $11 million. In 2007, Inkster recorded a season-best runner-up finish at the SemGroup Championship Presented by John Q. Hammons where she lost in a one-hole, sudden-death playoff to Mi Hyun Kim; carded her second LPGA career hole-in-one at the Michelob ULTRA Open at Kingsmill; made her seventh Solheim Cup appearance, where she scored three points for the victorious U.S. Team.
In 2008, her best finish was runner-up at the SemGroup Championship Presented by John Q. Hammons, where she lost a two-hole, sudden-death playoff to Paula Creamer; crossed the $12 million mark in career earnings at the Grand China Air LPGA.
Inkster has won the Samsung World Championship three times (1997-98, 2000) and has won the following tournaments twice: SAFECO Classic (1983, 1988); Nabisco Dinah Shore (1984, 1989); Lady Keystone Open (1985-86); Crestar Classic (1988-89); Atlantic City Classic (1986, 1988); Longs Drugs Challenge and McDonald’s LPGA Championship (1999-2000); and U.S. Women’s Open (1999, 2002).
In 2009, Inkster was selected for her eighth-career appearance on the U.S. Solheim Cup Team; at the age of 49 years, 1 month, 28 days at the start of the event, surpassed the victorious Team Captain Beth Daniel's record in 2007 as the oldest Solheim Cup competitor; Inkster posted a 1-2-1 record, thus becoming the highest points earner in U.S. Solheim Cup Team history; best finish was a tie for 10th at the CN Canadian Women's Open.
In 2010, Inkster lost by just one stroke to South Korean Jimin Kang to finish as runner up at the Sime Darby LPGA Malaysia. She also finished tied for ninth at the HSBC Women's Champions and at the P&G NW Arkansas Championship Presented by Walmart.
In 2011 Inkster competed on her ninth U.S. Solheim Cup Team, serving as the first-ever playing assistant captain. The 2012 season saw her achieve just 3 cuts as she had surgery to repair a torn tendon.