| Albert Oosthuizen |
Johannesburg, South Africa |
| Douglas Opfer |
Houston, Texas, United States |
| Bas Opgelder |
Hoofddorp, Netherlands |
| Gabriela Oprea |
Bucharest, Romania |
| Alina Orasanu |
Munich, Germany |
| Miriam Orejana |
Madrid, Spain |
| Michal Orenburg |
Tel Aviv, Israel |
| Diego Oreona |
A Coruña, Spain |
| Shawna Organisciak |
Denver, Colorado, United States |
| Vadim Orlov |
Moscow, Russian Federation |
| Dominic Orme |
Brighton, United Kingdom |
| Veruska Oropeza |
San Francisco, California, United States |
| Erich Orozco |
Atlanta, Georgia, United States |
| Tracy Orrison |
Washington D.C., , United States |
| Ronald Orsi |
New York, New York, United States |
