At the James A. Haley Veterans Hospital in Tampa, Fla, a program has been implemented to reduce the amount of potentially excessive laboratory testing. The major program components are a set of test frequency guidelines and a system of feedback to resident physicians that compares their test ordering patterns against the predetermined guidelines. The guidelines are analyte specific and differentiate between normal and abnormal test values reported during 1-day and 7-day time periods. The feedback process includes both systematic reporting of objective data and individual and group education and counseling sessions related to the appropriate use of laboratory tests. A reduction in the percentage of tests that fell outside the guidelines (outliers) was achieved following implementation of the program.