Sauber's technical director James Key has left the Swiss team to take up a new role in the UK.
Key, who has been with Sauber for two years, did not reveal what the new role was or whether it was in Formula 1.
F1 ON THE BBC IN 2012
- All the grands prix will be shown on BBC television
- Ten will be live - China (15 Apr); Spain (13 May); Monaco (27 May); Europe (24 Jun); Britain (8 Jul); Belgium (2 Sep); Singapore (23 Sep); Korea (14 Oct); Abu Dhabi (4 Nov); Brazil (25 Nov)
- The rest will have extended highlights - Asian time-zone races will be shown at 2pm; European time-zone races at 5.30pm
- All races will be live on 5 live and the BBC Sport website
- The website will have live video of the races that are live on TV and live audio and text commentary for all races
He said his time at Sauber had been "intense and interesting" as he managed their downsizing from the BMW works team to a private outfit.
Sauber said that Key's responsibilities would be shared by the heads of the four engineering departments.
The team's new car will be launched on Monday 6 February, ahead of the start of pre-season testing on 7 February in Jerez, Spain.