A program is described in which physicians prospectively review orders for the use of colony-stimulating factors (CSFs) at a tertiary-care private teaching hospital. Hospital officers and administrators and the heads of medical subspecialties were presented with three options for managing the use of CSFs. Prospective review by physicians was selected, and a task force of medical subspecialists was established to develop criteria for use and to review orders. Initially, every order was prospectively reviewed, but criteria were developed under which some orders do not require physician review. CSF use is documented retrospectively by a drug-use evaluation pharmacist and reviewed for appropriateness by the physician task force. Between March and October 1991, 115 patients were given courses of CSFs, and the use of the physician review system resulted in appropriate use of the drugs for 98% of the oncology patients and 61% of the patients infected with the human immunodeficiency virus. The prospective physician reviewer system has been accepted by the medical staff at the facility and has helped to ensure appropriate use of CSFs.