Pharmacist-managed drug therapy at a 205-bed nonprofit, general medical and surgical hospital is described. The pharmacy department provides a drug therapy management service in which clinical pharmacists initiate and adjust drug therapy and order laboratory tests according to criterion-based protocols. A physician requests initiation of the protocol and cosigns all orders written by pharmacists. The protocols for pharmacy-managed drug therapy are developed primarily by the clinical pharmacists and approved by the hospital's pharmacy and therapeutics and executive committees. They delineate specific indicators of the process (e.g., timely initiation of therapy) and outcome (e.g., clinical efficacy) of drug therapy management. These indicators are included in the record kept by the pharmacist for each patient treated in this program, and this documentation is reviewed daily. The same documentation is used in the drug-use evaluation (DUE) process. (Drugs for which drug therapy management protocols have been developed are among those selected for DUE.) In 1990, pharmacists managed 3616 courses of drug therapy by using approximately 100 drug protocols. The criterion-based drug therapy management service helps to fulfill the hospital's drug-use evaluation responsibilities by establishing specific process and outcome indicators, proposing drugs for DUE inclusion, and collecting data.