In an effort to more fully understand the contributions of the vehicular, environmental and driver characteristics to the frequency of rollover crashes, a dedicated database with a broad spectrum of variables, has been developed. This database, denoted by the acronym CARS (Crash Avoidance Rollover Study), includes data from approximately three thousand single vehicle rollover crashes. Vehicle types encompassed by this study include passenger cars, light trucks, utility vehictes and vans. The contents of the CARS database were collected over a one and a half year period by trained investigators from the Maryland State Police and supplemented by information derived from analyses by NHTSA staff. This database contains all levels of reported accident and injury severity.