| Omodei, Raymond | Raymond Omodei | Designer, Director | 1974 - 2001 | 5 | |
| Olroth-Hackenbroch, Gisela | Gisela Olroth-Hackenbroch | Designer, Director | 2011 | 2 | |
| Ockel, Reinhold | Reinhold Ockel | Designer, Director | 1927 - 1942 | 2 | |
| Orr, Lynn E. | Lynn E. Orr | Designer, Director, Lighting Designer | 1937 | 3 | |
| O'Brien, Dan | Dan O'Brien | Designer, Lighting Designer | 2008 | 2 | |
| O'Neill, Chris | Chris O'Neill | Designer, Lighting Designer | 2011 | 2 | |
| Olmsted, Richard | Richard Olmsted | Designer, Lighting Designer | 2002 - 2003 | 3 | |
| Oggenfuss, Michael | Michael Oggenfuss | Designer, Lighting Designer | 2002 - 2004 | 66 | 1 |
| O'Connor, Boardman | Boardman O'Connor | Designer, Lighting Designer | 1961 | 2 | |
| Ohgitani, Kunio | Kunio Ohgitani | Director | 1980 | 1 | |
| Osmanov, Bahram | Bahram Osmanov | Director | 2006 | 1 | |
| Olsson, Lennart | Lennart Olsson | Director | 1971 - 1987 | 4 | 1 |
| Olsten, Agnieszka | Agnieszka Olsten | Director | 2006 - 2009 | 7 | 1 |
| Orsky, Gudrun | Gudrun Orsky | Director | 2004 | 1 | 1 |
| Ott, Sharon | Sharon Ott | Director | 1993 - 1997 | 3 | 1 |
| Orsza-Łukasiewicz, Janina | Janina Orsza-Łukasiewicz | Director | 1972 | 1 | |
| Oittinen, Tytti | Tytti Oittinen | Director | 1992 - 1994 | 2 | 1 |
| O'Connor, John | John O'Connor | Director | 2003 | 1 | |
| Orlandini, Claudio | Claudio Orlandini | Director | 2011 | 1 | |
| Ochandiano, Amelia | Amelia Ochandiano | Director | 2010 - 2011 | 40 | |
| O'Leary, Bridget Kathleen | Bridget Kathleen O'Leary | Director | 2011 | 1 | |
| Oscar, Harry | Harry Oscar | Director | 1900 | 1 | |
| Oberländer, Hans | Hans Oberländer | Director | 1904 - 1908 | 2 | |
| O'Neil, Barry | Barry O'Neil | Director | 1909 | 1 | |
| Osanai, Kaoru | Kaoru Osanai | Director | 1909 - 1928 | 6 | 1 |
| Olafsen, Carl Fredrik | Carl Fredrik Olafsen | Director | 2010 | 1 | |
| Ostrowsky, Hartmut | Hartmut Ostrowsky | Director | 1975 | 1 | |
| Orešković, Želimir | Želimir Orešković | Director | 1975 - 1989 | 3 | 1 |
| Ognjanović, Aleksandar | Aleksandar Ognjanović | Director | 1955 - 1979 | 4 | |
| Olschok, Herbert | Herbert Olschok | Director | 1988 - 2014 | 5 | |
| Oglesby, Marshall | Marshall Oglesby | Director | 1973 | 1 | |
| Oľha, Matúš | Matúš Oľha | Director | 1993 | 1 | |
| Owusu, Janet | Janet Owusu | Director | 2006 | 1 | 1 |
| Ojala, Timo | Timo Ojala | Director | 1985 | 1 | |
| O'Brien, Jack | Jack O'Brien | Director | 1990 | 1 | 1 |
| Oswald, David | David Oswald | Director | 1993 | 1 | |
| Orlac, S. | S. Orlac | Director | 1995 | 1 | |
| Ongley, Warwick | Warwick Ongley | Director | 1969 | 1 | |
| Oelschlegel, Vera | Vera Oelschlegel | Director | 1997 - 2000 | 52 | |
| Ocel, Tim | Tim Ocel | Director | 2002 | 1 | |
| O'Connell, Robert, A. | Robert A. O'Connell | Director | 2003 | 1 | |
| Onat, Cigdem | Cigdem Onat | Director | 2005 | 1 | |
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