In 1993 she won the
Swedish Junior Match-play Championship, which at the time, due to Sweden's "open golf"-policy was not restricted to amateurs only, but it was without prize-money and unique that it was won by a young professional. From 1992 to 1994, Gustafson played 12
Telia Tour and four
Ladies European Tour tournaments. On the Telia Tour, she had six top-10 finishes. Her best finish on the Ladies European Tour was a 22nd at her home tournament in Sweden. 1995 saw her join the Ladies European Tour gaining two top-10 finishes in 13 starts. 1996 was her first full year on the Ladies European Tour. She gained her first professional wins, winning once on the Telia Tour at the
Rörstrand Ladies Open and once on the Ladies European Tour at the Déesse Ladies Swiss Open. In 1997 she earned her first win on the Ladies Asian Tour at the Thailand Ladies Open and finished T40th at LPGA Q School to earn non-exempt status for 1998. and made her debut in the
Solheim Cup, replacing the injured
Trish Johnson at the last minute. During 1999, Gustafson played on both the LPGA and Ladies European Tours. Her best result was a tie for second at the
Ladies' German Open on the Ladies European Tour. and added a second LPGA title at the co-sanctioned Women's British Open. She had two other wins in Europe at the
Ladies Italian Open and at the
Waterford Crystal Ladies' Irish Open, and partnered with
Carin Koch to win the inaugural
TSN Ladies World Cup Golf. She also won 2 and a half out of a possible four points in Europe's Solheim Cup victory at Loch Lomond. In 2001 Gustafson won once on both the LPGA Tour at the
Subaru Memorial of Naples and Ladies European Tour at the
AAMI Women's Australian Open crossing the LPGA Tour career $1million earnings mark. The defence of her LPGA title ended with her losing in a playoff to
Annika Sörenstam. In 2002, she played seven LET events, posting four top-10 finishes, ending the season with one victory at the Biarritz Ladies Classic and third place in the Order of Merit as well as winning the Vivien Saunders Stroke average trophy. and secured another LET Order of Merit title. She also won her third LET Players' Player of the Year award and the Vivien Saunders Stroke Average trophy. She won the Samsung World Championship on the LPGA tour, her 4th LPGA win, crossing the $2million LPGA Tour career earnings mark. She became the first woman to compete in a men's Japan Golf Tour event, and was part of the winning European
Solheim Cup team in her native
Sweden. During 2004 Gustafson struggled with illness due to
deep vein thrombosis in her leg. Three LET events in 2005 yielded a second-place finish at the Weetabix Women's British Open and 3rd place on the LET Money List. On the LPGA Tour she had seven top 10 finishes and tied her career low round of 64 at the
Wendy's Championship for Children. and was a member of the winning International Team in the inaugural
Lexus Cup. In 2006 Gustafson played in just three LET events but finished fourth on the New Star Money List after claiming her first victory in almost three years at the
Siemens Austrian Ladies Golf Open at Golfclub Fohrenwald in
Wiener Neustadt in Austria. This win gave her the point she needed to become a Life Member of the LET. She earned her thirteenth LET win in 2007 at the
De Vere Ladies Scottish Open. Gustafson was a member of the European
Solheim Cup team in
1998,
2000,
2002,
2003,
2005,
2007,
2009 and
2011. ==Awards, honors==