OBJECTIVE To develop a physician office-based pharmaceutical care practice and evaluate the impact on the participating physicians, their staff, and patients. METHODS Internal medicine physician office. METHODS Two physicians and two nurses practice in a medical office complex in a rural setting in eastern Washington. METHODS Development of an experimental pharmaceutical care program in which a registered pharmacist works in a physician office to evaluate the medication needs of patients and to provide pharmaceutical care and medication information to health professionals and patients. METHODS Functions and interventions performed by the pharmacist; types of disease states in patients that were confronted by the pharmacist; summary of time spent with patients; and attitudes of physicians and patients concerning the pharmacist interventions. RESULTS 660 pharmacist interventions or functions occurred during the seven months of the project. Of 107 recommendations to the physicians concerning changes in therapy, 89 were accepted. Patients suffered from 53 different disease states that were evaluated by the pharmacist. The pharmacist spent from less than 5 minutes to more than an hour with individual patients, 5 to 15 minutes with the majority of patients. Both patients and physicians were impressed with the service and strongly desired to have it continued. CONCLUSIONS There is a career opportunity for pharmacists to provide pharmaceutical care in the setting of a physician office practice. Many of the barriers to providing pharmaceutical care can be eliminated or diminished in this setting.