Lindsay Davenport was the defending champion, but lost to Jennifer Capriati in the semifinals, in a rematch of their semifinal at the 2000 Australian Open.
Andres Gomez was the defending champion but did not compete that year.
Martina Navratilova was the defending champion, but she was defeated by Hana Mandlíková in the final, 7–6(7–3), 1–6, 7–6(7–2).
Cara Black and Liezel Huber were the defending champions, but lost in the quarterfinals to sisters Alona Bondarenko and Kateryna Bondarenko.
Lleyton Hewitt was the defending champion but lost in the semifinals to Francisco Clavet.
Richard Krajicek was the defending champion, but lost in the semifinals to Jan Siemerink.
Andriy Medvedev was the defending champion but lost in the second round to Jordi Burillo.
Andre Agassi was the defending champion but did not compete that year.
Mats Wilander was the defending champion but lost in the semifinals to Stefan Edberg.
Lindsay Davenport was the defending champion but lost in the semifinals to Mary Pierce.
The 1999 Bausch & Lomb Championships – Singles was the singles event of the twentieth edition of the Bausch & Lomb Championships; a WTA Tier II tournament held in Amelia Island, Florida, United States, played on green clay. Mary Pierce was the defending champion but lost in the quarterfinals to Conchita Martínez.
Manuela Maleeva was the defending champion but lost in the second round to Catarina Lindqvist.
Thomas Enqvist was the defending champion but lost in the second round to Tomás Carbonell.
Serena Williams and Venus Williams were the defending champions, but both withdrew from the tournament with a pulmonary embolism and a hip injury, respectively.
In the final, Andrea Hlaváčková and Lucie Hradecká defeated 7th seeded Sania Mirza and Elena Vesnina in straight sets, 6–4, 6–3.
The 1999 Italian Open – Singles was the singles event of the fifty-fifth edition of the tennis tournament played at Rome, Italy, the most prestigious tennis tournament in Southern Europe. It was the fifth WTA Tier I tournament of the year, and part of the European claycourt season. Martina Hingis was the defending champion but lost in the semifinals to Venus Williams.
Andrea Hlaváčková and Lucie Hradecká were the defending champions, but lost in the semifinals to Maria Kirilenko and Nadia Petrova.
Sara Errani and Roberta Vinci won the tournament by defeating Maria Kirilenko and Nadia Petrova 4–6, 6–4, 6–2 in the final.
The 1999 Acura Classic – Singles was the singles event of the twentieth edition of the third tournament in the US Open Series.
Fabio Fognini was the defending champion, but lost in the semifinals to Roberto Bautista Agut.
Bautista Agut went on to win the title, defeating Lukáš Rosol in the final, 6–3, 4–6, 6–2.
Fernando Verdasco was the defending champion, but lost to Sam Querrey in the semifinals.
Jack Sock won his first ATP singles title, defeating Querrey in the final, 7–6(11–9), 7–6(7–2).
Richard Gasquet was the defending champion, but lost to Jordan Thompson in the semifinals.
