This study uses data from the 1997 National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey to describe nonfederal physician office, hospital outpatient, and emergency department visits involving physician assistants (PAs). Of an estimated 959 million visits to health care practitioners, 2.55% (an estimated 24,532,000) involved PAs. Diagnoses associated with ambulatory care visits involving PAs included well-infant and well-child examinations and the care of uncomplicated injuries or wounds and respiratory tract infections. On average, 3.1 medications were ordered or provided at a visit with a PA. The problems that PAs address are similar across the 3 ambulatory care settings analyzed, with some expected variation between physician office and emergency department visits. Generally, ambulatory care visits with PAs mirror visits with all health care providers who practice ambulatory care medicine. PA education programs should ensure that students can competently perform the skills needed for typical ambulatory care practice.