Whilst rail travel is one of the safest forms of public transport available today, recent accidents which have occurred both in the United Kingdom and abroad have raised considerable public concern over safety procedures.

The signalling system used to control train movements has played a major role in ensuring the safety of trains on our railways. However, this role has generated extensive debate in the media and many established practices have been called into question. Of particular concern is the integrity of modern signalling and its ability to enforce the observance of signals by train drivers.