Background: Computerized clinical outcomes measurement systems are now routinely available to help physicians and hospital administrators assess and improve the quality of care in their organizations. The Voluntary Hospitals of America, Pennsylvania (VHA/PA), used MedisGroups data to help understand the processes of care that contributed to different clinical outcomes at different network hospitals. Method: A physician subcommittee decided early on (1) to focus on the best outcomes rather than the poorest and (2) to determine the variations in processes of care that might have led to either superior or inferior clinical outcomes. For two common procedures, appendectomy and cesarean section, the subcommittee identified variation within comparative outcomes data, evaluated that variation, and studied and communicated to the rest of the hospital network the process that produced the best outcomes. Conclusion: These pilot projects set the stage for current clinical benchmarking within the VHA/PA system. The committee of physicians learned that each hospital develops its own approach to common clinical conditions. These approaches become standardized at each hospital in the form of institutional attitudes, beliefs, policies, and procedures. The methods of evaluation and treatment by hospital staff can significantly alter the clinical outcomes for the populations served.