Motor manufacturers spend millions of pounds on research and development and part of that money goes on the practical road testing of vehicles. William Woollard looks at Britain's longest test track to find out if the expense and effort is justified. Jackie Stewart looks ahead to the new law to make the wearing of seat belts compulsory. If you thought it was difficult enough to take your driving test, Sue Baker finds out how the professionals do it at the Army School of Mechanical Transport.

From midnight on 30 January it becomes law for most drivers and front-seat passengers to wear a seat belt. But who is exempt? How are the police going to administer the law? What happens if you are caught not wearing a seat belt? Answering questions from the motoring public are Jackie Stewart long-time advocate of seat belts Dr Murray Mackay, Head of the Accident Research Unit, University of Birmingham and Roger Birch, Chief Constable, Warwickshire Constabulary.

The emphasis this week is on performance cars. Jackie Stewart shows William Woollard that what he learnt as a racing driver can help people to drive more safely on the roads. And Sue Baker tests the new Renault GTA V6 Turbo. But, with so many powerful cars on the market at the moment, do the glossy ads that sell them actually encourage drivers to break the law? Top Gear talks to the ad men and their critics.