Rachel McQuillan and Lisa McShea were the defending champions but lost in the first round to Kerry-Anne Guse and Alicia Molik.
Serena and Venus Williams defeated Julie Halard-Decugis and Ai Sugiyama in the final, 6-3, 6-2 to win the ladies' doubles tennis title at the 2000 Wimbledon Championships. They became the first pair of sisters to win the title. It was their third major title in doubles, and the third component in an eventual career Golden Slam in doubles. The Williams sisters had only played three events thus far into the season, and only entered the draw via a wildcard.
Kimiko Date and Ai Sugiyama were the defending champions but only Sugiyama competed that year with Shinobu Asagoe.
Alexia Dechaume-Balleret and Rika Hiraki were the defending champions but only Hiraki competed that year with Amy Frazier.
The 1999 Japan Open Tennis Championships was a tennis tournament played on outdoor hard courts at the Ariake Coliseum in Tokyo, Japan that was part of the International Series Gold of the 1999 ATP Tour and of Tier III of the 1999 WTA Tour. The tournament was held from April 12 through April 18, 1999. Nicolas Kiefer and Amy Frazier won the singles titles.
The 1999 Japan Open Tennis Championships women's singles was the women's singles event of the twenty-fifth edition of the Japan Open; a WTA Tier III tournament held in Tokyo, Japan. Ai Sugiyama was the defending champion but lost in the final 6–2, 6–2 against Amy Frazier.
The 1999 Direct Line International Championships doubles was the doubles event of the twenty-fifth edition of the Eastbourne International, a WTA Tier II tennis tournament held in Eastbourne, England and part of the European grass court season. Mariaan de Swardt and Jana Novotná were the defending doubles champions but each competed with different partners in 1999. De Swardt partnered Elena Tatarkova and reached the semifinals where they lost to Martina Hingis and Anna Kournikova. Novotná teamed with Natasha Zvereva and they retired in the final to Hingis and Kournikova after losing the first set 4–6.
The 1999 US Open mixed doubles was the mixed doubles event of the hundred-and-ninth edition of the US Open, the fourth and last Grand Slam of the year. Serena Williams and Max Mirnyi were the defending champions but did not compete that year.
The 1999 French Open mixed doubles was the mixed event of the ninety-eighth edition of the French Open, the second Grand Slam of the year. Justin Gimelstob and Venus Williams were the defending champions, but they did not compete this year.
Serena and Venus Williams defeated Chanda Rubin and Sandrine Testud in the final, 4–6, 6–1, 6–4 to win the women's doubles tennis title at the 1999 US Open. It was the second doubles major title for the Williams sisters, and their second step towards completing the career Golden Slam in doubles.
The 1999 du Maurier Open doubles was the doubles event of the one hundred and tenth edition of the Canadian Open; a WTA Tier I tournament and the most prestigious women's tennis tournament held in Canada.
There was no defending champion, due to the cancellation of the semifinals in 1998 due to rain.
Lindsay Davenport and Jana Novotná were the defending champions, but they did not play together this year. Davenport played with Natasha Zvereva as the second seed, and Novotná played with Martina Hingis as the first seed.
The 1999 DFS Classic singles was the singles event of the seventeenth edition of the Aegon Classic, a WTA Tier III tournament held in Birmingham, England, United Kingdom and part of the European grass court season. Els Callens and Julie Halard-Decugis were the defending champions but did not return to defend their title.
Serena and Venus Williams defeated Lindsay Davenport and Corina Morariu in the final, 6–2, 4–6, 6–4 to win the women's doubles tennis title at the 2001 Australian Open. It was the Williams sisters' fourth major doubles title, and they completed the career Golden Slam in doubles with the win.
The 1999 Toyota Princess Cup – Doubles was the tennis doubles event of the third edition of the first hardcourt tournament after the US Open. Anna Kournikova and Monica Seles were the defending champions, but neither competed this time.
Gigi Fernández and Natasha Zvereva were the defending champions but Fernández retired at the end of the 1997 season.
Serena Williams and Venus Williams were the defending champions, but did not compete this year.
Martina Hingis and Anna Kournikova were the defending champions, but competed this year with different partners. Hingis partnered with Mary Pierce and finished the tournament as runners-up, while Kournikova teamed up with Barbara Schett and lost in semifinals to Lisa Raymond and Rennae Stubbs.
Martina Hingis and Jana Novotná were the defending champions, but none of them competed this year. Novotná also retired at the end of the 1999 season.
Corina Morariu 
Catherine Barclay 
