| Event | Venue | Chair(s) | OMCOS |
|---|---|---|---|
| OMCOS 1,1981 | Ft. Collins | John Stille, Lou Hegedus | - |
| OMCOS 2, 1983 | Dijon | Jean Tirouflet | - |
| OMCOS 3, 1985 | Kyoto | Hitoshi Nozaki | - |
| OMCOS 4, 1987 | Vancouver | Gary Posner, Mike Fryzuk | - |
| OMCOS 5, 1989 | Firenze | G. Casnati, Alfredo Ricci, Piero Salvadori | - |
| OMCOS 6, 1991 | Utrecht | Gerard VanKoten | - |
| OMCOS 7, 1993 | Kobe | Shun-ichi Murahashi | - |
| OMCOS 8, 1995 | Santa Barbara | Bruce Lipshutz | - |
| OMCOS 9, 1997 | Göttingen | Armin DeMeijere, Reinhart Hoffmann | Shu Kobayashi |
| OMCOS 10, 1999 | Versailles | Jean Pierre Genet, Pierre Dixneuf | Erick Carreira |
| OMCOS 11, 2001 | Taipei | Tien-Yau Luh | Greg Fu |
| OMCOS 12, 2003 | Toronto | Mark Lautens | Kyoto Nozaki |
| OMCOS 13, 2005 | Geneva | Peter Kündig, Alex Alexakis | Shengming Ma |
| OMCOS 14, 2007 | Nara | Koichi Oshima | Dean Toste |
| OMCOS 15, 2009 | Glasgow | Pavel Kocovsky | Keith Fagnou |
| OMCOS 16, 2011 | Shanghai | Shengming Ma, Kuiling Ding | Frank Glorius |
| OMCOS 17, 2013 | Ft. Collins | Tom Rovis | Zhang-Jie Shi |
| OMCOS 18, 2015 | Sitges | Antonio Echavarren | Melanie Saford |
| OMCOS 19, 2017 | Jeju | Sukbok Chang, Chulbom Lee | Ruben Martin |
| OMCOS 20, 2019 | Heidelberg | Stephen Hashmi | Sarah Reismann |
See some of OMCOS’ Magic Moments here: