Mr Hoon, a pro-European Blairite, is widely seen as a capable and safe pair of hands. But his tenure at the MOD has not been without controversy. He has had to tackle difficult issues such as gays in the military and the continuing debate over the future shape of British forces. He has also been at the forefront of the UK's involvement in the planned European "Rapid Reaction Force".
The decision to privatise the top secret defence research agency, DERA, has proved controversial while the UK’s military action to prop up the Sierra Leone government saw him face a Commons grilling.
Before joining Parliament, Mr Hoon spent a decade as an MEP – making him perhaps ideally suited to deal with european defence and co-operation issues.