The Oxfordshire Area Ambulance Service in common with all civilized ambulance services in the western world, has made extensive plans for dealing with major disasters. These plans include the use of specialized vehicles which attend the scene of a disaster in an effort to provide medical expertise and equipment together with some hospital type facilities to commence treatment for the severely injured casualties. In the late '70s, the ambulance service in Oxfordshire purchased a caravan, at ridiculously low cost, from the local regional blood transfusion service which was no longer required. This caravan was converted for use as a three-bedded medical aid unit to be towed and parked near to the scene of the disaster. The unit was superbly equipped, but suffered severely from its size, and also from the need to tow it to its destination. It was a slow and ponderous vehicle but nevertheless it performed a useful service at static displays and exhibitions where the possibility of a major incident was anticipated. It was regularly to be found as a part of the medical presence at the local Royal Air Force establishments during their open days and flying displays. It had many advantages, such as good lighting and ventilation, and was well equipped, but it was very slow to mobilize and move and also because of its size and weight, it was unstable unless properly and carefully parked on a firm surface.