Stage Definition Working Groups
| Hettangian | None presently |
| Sinemurian | Gerd Bloos |
| Pliensbachian | Christian Meister |
| Toarcian | Rogério Rocha |
| Aalenian | Maria Helena Henriques |
| Bajocian | András Galacz |
| Bathonian | Sixto Fernandez Lopez |
| Callovian | Eckhard Mönnig |
| Oxfordian | Guillermo Melendez |
| Kimmeridgian | Andrzej Wierzbowski |
| Tithonian | Federico Oloriz |
Topical Working Groups
| Geoconservation | Kevin Page |
| Liaison | Robert Chandler |