New Zealand's two assistant coaches are former All Blacks Scott Robertson and Leon MacDonald.
Samoa are coached by former loose forward and captain Semo Sititi, while former NZ Sevens rep Orene Ai'i is one of his assistants.
Also joining the management, albeit in more of a liaison role, is former Manu Samoa lock Mark Birtwistle.
Fiji's assistant coach is former NZ Sevens rep Iliesa Tanivula, while former All Blacks loosie Mike Brewer is helping Ireland in an unofficial capacity. His son Harrison is one of the midfielders.
France manager Fabien Pelous was one of their great locks and assistant coach Olivier Magne was a quality openside flanker for nearly 100 tests.
Italy's manager, Claudio Appiani, was briefly a wing for the Azzurri from 1976 to 1978.
Greig Oliver is the Ireland assistant coach, but played three tests for Scotland.
Famous coaches
Fabien Pelous (France) 118 tests
Alessandro Troncon (Italy) 101 tests
Olivier Magne (France) 89 tests
Leon MacDonald (New Zealand) 56 tests
Mark Taylor (Wales) 52 tests
Sean Lineen (Scotland) 29 tests
Scott Robertson (New Zealand) 23 tests
Fabio Roselli (Italy) 16 tests
Dawie Theron (South Africa) 13 tests
Claudio Appiani (Italy) 5 tests
Greig Oliver (Scotland) 3 tests
Byron Hayward (Wales) 2 tests
Nick Walshe (England) 2 tests
Cameron Blades (Australia) 1 test.