This paper addresses the potential utility of statewide uniform hospital discharge abstract data for trauma research and system evaluation. Currently 28 states require that uniform hospital discharge abstract data be collected on all acute care hospitalizations. The recent development of a computerized conversion table that translates ICD-9CM coded discharge diagnoses into AIS body region and severity codes has led to new applications of these databases, providing populationbased data specific to the severity of injuries. The 1986 Maryland State Uniform Discharge Abstract database, which includes 32,921 discharges with a traumatic injury listed as principal diagnosis are used to examine the utility of hospital discharge data and the ICD-AIS conversion for two specific applications. First, the data are analyzed for monitoring trends in the incidence of head injury. Such analyses have the potential for expanding our understanding of the epidemiology of injuries. A second area of application is in the evaluation of the performance of regionalized systems of trauma care. With the continuing attention focused on the regionalization of acute trauma care, it is becoming increasingly important to develop methods of ongoing evaluation which rely on routinely collected data. The advantages and limitations of both the database and ICDAIS conversion table for these applications will be discussed and recommendations made for improvements through linkage of databases and better injury coding.