The 1990 Cincinnati Open, was a tennis tournament played on outdoor hard courts. It was the 91st edition of the tournament and was part of the 1990 ATP Tour. It took place in Cincinnati, Ohio, United States from August 13 through August 20, 1990. Ken Flach and Robert Seguso were the defending champions, but lost in the second round to Sven Salumaa and Byron Talbot. Darren Cahill and Mark Kratzmann won in the final, 7–6, 6–2, against Neil Broad and Gary Muller.
Ken Flach and Robert Seguso were the defending champions but lost in the semifinals to John Fitzgerald and Anders Järryd.
John Fitzgerald and Anders Järryd were the defending champions but lost in the first round to Jonathan Canter and Bruce Derlin.
John McEnroe and Michael Stich defeated Jim Grabb and Richey Reneberg in the final, 5–7, 7–6(7–5), 3–6, 7–6(7–5), 19–17 to win the gentlemen's doubles title at the 1992 Wimbledon Championships.
Rick Leach and Jim Pugh were the defending champions, but lost in the semifinals to Grant Connell and Glenn Michibata.
Pieter Aldrich and Danie Visser won the title, defeating Connell and Michibata 6–4, 4–6, 6–1, 6–4, in the final.
Grant Connell and Glenn Michibata were the defending champions, but lost in the quarterfinals this year.
Guy Forget and Jakob Hlasek were the defending champions, but did not participate this year.
Kelly Jones and Robert Van't Hof were the defending champions, but Jones did not participate this year. Van't Hof partnered Brian Garrow, losing in the first round.
The men's doubles competition at the 1992 French Open was held between 25 May and 7 June 1992 on the outdoor clay courts at the Stade Roland Garros in Paris, France. The unseeded team of Jakob Hlasek and Marc Rosset won the title, defeating David Adams and Andrei Olhovskiy in the final.
The men's doubles tournament at the 1989 French Open was held from 29 May until 11 June 1989 on the outdoor clay courts at the Stade Roland Garros in Paris, France. Jim Grabb and Patrick McEnroe won the title, defeating Mansour Bahrami and Éric Winogradsky in the final.
The men's doubles tournament at the 1990 French Open was held from 28 May until 10 June 1990 on the outdoor clay courts at the Stade Roland Garros in Paris, France. Sergio Casal and Emilio Sánchez won the title, defeating Goran Ivanišević and Petr Korda in the final.
The men's doubles event at the 1991 French Open tennis tournament was held from 27 May until 9 June 1991 on the outdoor clay courts at the Stade Roland Garros in Paris, France. John Fitzgerald and Anders Järryd won the title, defeating Goran Ivanišević and Petr Korda in the final.
Andre Agassi and Petr Korda were the defending champions, but Agassi did not compete this year. Korda teamed up with Stefan Edberg and lost in second round to Cyril Suk and Daniel Vacek.
Neil Broad and Gary Muller were the defending champions, but lost in the second round to Kent Kinnear and Brad Pearce.
Andre Agassi was the defending champion and successfully defended his title, by defeating Petr Korda 6–3, 6–4 in the final.
Grant Connell and Glenn Michibata were the defending champions, but lost in the semifinals to tournament runners-up Ken Flach and Robert Seguso.
Patrick Galbraith and Todd Witsken were the defending champions, but competed this year with different partners.
Todd Woodbridge and Mark Woodforde were the defending champions, but Woodbridge did not compete this year. Woodforde teamed up with Jason Stoltenberg and lost in the first round to tournament winners Andre Agassi and Petr Korda.
Patrick Galbraith and Danie Visser were the defending champions, but competed this year with different partners. Galbraith teamed up with Grant Connell and lost in the semifinals to Jim Courier and Mark Knowles, while Visser teamed up with Laurie Warder and lost in the second round, also to Courier and Knowles.
Paul Annacone and David Wheaton were the defending champions, but Wheaton chose not to participate. Annacone partnered with Doug Flach, but lost to Jim Grabb and Richey Reneberg in the first round.
Ken Flach 
Grant Connell 
