| Name | Functions | Event Dates | Events | Resources  | ||
|---|---|---|---|---|---|---|
| Thomas Olsson | Actor | 1998 - 2017 | 3 | 1 | ||
| Gunilla Orvelius | Actor | 1992 - 2002 | 27 | 1 | ||
| Elvira Onetto | Actor | 2009 - 2011 | 13 | 1 | ||
| Jakob Oschlag | Adaptation, Director | 1977 - 2001 | 8 | 1 | ||
| Želimir Orešković | Director | 1975 - 1989 | 3 | 1 | ||
| Virgil Ogăşanu | Actor | 1969 - 2006 | 6 | 1 | ||
| Eva Opaker | Actor | 1973 | 1 | 1 | ||
| Ladislav Obuch | Translator | 1955 - 2021 | 14 | 1 | ||
| Ilaria Occhini | Actor | 1981 - 2005 | 19 | 1 | ||
| Kipp Osborne | Actor | 1976 | 1 | 1 | ||
| Jens Okking | Actor | 1979 - 1984 | 4 | 1 | ||
| John Osborne | Adaptation, Translator | 1972 - 2011 | 8 | 1 | ||
| Patricia O'Donnell | Actor | 1981 | 4 | 1 | ||
| Richard Ooms | Actor | 1983 - 2008 | 10 | 1 | ||
| Henning Olesen | Actor | 1983 - 2010 | 3 | 1 | ||
| Ary Oechslin | Costume Designer, Designer | 1952 - 1978 | 11 | 1 | ||
| Taisto-Bertil Orsmaa | Adaptation, Director | 1983 - 1996 | 3 | 1 | ||
| Janet Owusu | Director | 2006 | 1 | 1 | ||
| Joanna O'Connor | Actor | 2007 - 2021 | 4 | 1 | ||
| Sonja Oppenhagen | Actor | 1982 - 1993 | 4 | 1 | ||
| Alejandra Oviedo | Actor | 2012 - 2013 | 3 | 1 | ||
| Judith Olauson | Actor | 1984 | 1 | 1 | ||
| Christopher Oden | Actor, Director | 1984 - 2001 | 6 | 1 | ||
| L'ubica Obuchová | Costume Designer | 1985 | 1 | 1 | ||
| Trygve Olsen | Lighting Designer | 1985 - 1987 | 3 | 1 | ||
| Robert Ornbo | Lighting Designer | 1978 - 1987 | 2 | 1 | ||
| Jack O'Brien | Director | 1990 - 2025 | 2 | 1 | ||
| Daniel O'Brien | Actor | 2012 | 1 | 1 | ||
| Nick Ormerod | Designer | 1990 | 1 | 1 | ||
| Trevor H. Olsen | Actor | 1991 | 1 | 1 | ||
| Anna Ottmann | Actor | 1992 - 2000 | 3 | 1 | ||
| Natalie Ogle | Actor | 1988 | 1 | 1 | ||
| Brendan O'Hea | Actor | 1993 - 1999 | 6 | 1 | ||
| Bulle Ogier | Actor | 1993 | 4 | 1 | ||
| Ádám Ottlik | Actor | 1996 - 2008 | 2 | 1 | ||
| Ruth Orthmann | Translator | 1994 | 1 | 1 | ||
| Friederike Ott | Actor | 2014 - 2016 | 12 | 1 | ||
| David Osmond | Actor | 2012 | 1 | 1 | ||
| Patrick O'Kane | Actor | 2000 | 1 | 1 | ||
| Thomas Oglesby | Actor | 1977 - 1980 | 2 | 1 | ||
| Huguette Oligny | Actor | 1996 | 1 | 1 | ||
| Louise Søeborg Ohlsen | Actor | 1995 | 1 | 1 | ||