Crashworthiness ratings measure the relative safety of vehicles in preventing severe injury to their own drivers in crashes whilst aggressivity ratings measure the serious injury risk vehicles pose to drivers of other vehicles with which they collide. Crashworthiness and aggressivity ratings for 1982-2000 model vehicles were developed based on data on crashes in Victoria and New South Wales during 1987-2000 and in Queensland and Western Australia during 1991-2000. Crashworthiness and aggressivity were measured by a combination of injury severity (of injured drivers) and injury risk (of drivers involved in crashes). The ratings were adjusted for the driver sex and age, the speed limit at the crash location, the number of vehicles involved, the state in which the crash occurred and the year in which the crash occurred. These factors were strongly related to injury risk and/or severity for both aggressivity and crashworthiness. Both ratings estimate, with the appropriate focus, the risk of a driver being killed or admitted to hospital when involved in a tow-away crash, to a degree of accuracy represented by the confidence limits of the rating in each case. The crashworthiness estimates and their associated confidence limits were sufficiently sensitive that they were able to identify 95 models of passenger cars, four-wheel drive vehicles, passenger vans and light commercial vehicles that have superior or inferior crashworthiness characteristics compared with the average vehicle. Aggressivity rating estimates and their associated confidence limits were sufficiently sensitive that they were able to identify 48 models of passenger cars, four-wheel drive vehicles, passenger vans and light commercial vehicles that have superior or inferior aggressivity characteristics compared with the average vehicle. Also investigated was the relationship between vehicle crashworthiness and the year of manufacture of Australian passenger and light commercial vehicles manufactured from 1964 to 2000. Trends were examined by year of manufacture both for the fleet as a whole and by market group for vehicles manufactured from 1982 to 2000. The results of this report are based on a number of assumptions and warrant a number of qualifications that should be noted.