Nadia Petrova and Martina Navratilova were the defending champions, but Navratilova retired from the sport on September 10, 2006, and only Petrova competed that year.
Petrova partnered with Svetlana Kuznetsova, but lost in the quarterfinals to Nathalie Dechy and Sun Tiantian.
Nathalie Dechy and Dinara Safina were the defending champions, but Safina chose not to participate, and only Dechy competed that year.
Dechy partnered with Casey Dellacqua, but lost in the first round to Klaudia Jans and Alicja Rosolska.
In the 2001 DFS Classic women's tennis tournament, Lisa Raymond was the defending singles champion, but was defeated in the semifinals by Nathalie Tauziat.
Venus Williams was the defending champion, but chose not to participate that year.
Nathalie Dechy and Mara Santangelo were the defending champions, but Dechy retired from tennis before being able to defend the title, and Santangelo chose not to participate this year.
There was no defending champion, due to the cancellation of the semifinals in 1998 due to rain.
Julie Halard-Decugis was the defending champion, but was defeated in the quarterfinals by Tamarine Tanasugarn.
Daniela Hantuchová and Ai Sugiyama were the defending champions but decided not to defend the title together. Hantuchová chose to play with Nadia Petrova while Sugiyama played with Katarina Srebotnik. Both lost in the second round. Nathalie Dechy and Mara Santangelo won the title by defeating Tathiana Garbin and Roberta Vinci 6–4, 6–1 in the final.
Maria Sharapova was the defending champion, but lost to Martina Hingis in the semifinal.
Chanda Rubin was the defending champion, but decided not to participate this year.
Lindsay Davenport was the defending champion, but could not participate due to a back injury.
Jennifer Capriati was the defending champion, but lost in quarterfinals to Nathalie Dechy.
Ai Sugiyama was the defending champion, but lost in first round to Dinara Safina.
Kim Clijsters was the defending champion, but lost in quarterfinals to Venus Williams.
Venus Williams was the defending champion and successfully defended her title by defeating Kim Clijsters 6–2, 6–4 in the final.
Gisela Dulko and Květa Peschke were the defending champions, but competed this year with different partners. Dulko teamed up with Michaëlla Krajicek and lost in first round to Eleni Daniilidou and Jasmin Wöhr. Peschke teamed up with Francesca Schiavone, but the pair withdrew before their semifinal match against Corina Morariu and Katarina Srebotnik, as Schiavone had injured her right knee.
Katarina Srebotnik was the defending champion, but lost in first round to Seda Noorlander.
Anabel Medina Garrigues was the defending champion, but was defeated in the semifinals by Peng Shuai. Nicole Vaidišová won the title, defeating Peng in the final 7–6(9–7), 6–3.
Venus Williams was the defending champion, but did not compete this year due to a tendinitis in her left wrist.
Karina Habšudová and Daniela Hantuchová were the defending champions but chose to compete at Zürich during the same week, with different partners.
Nathalie Dechy 
Marie-Gaïané Mikaelian 
