To determine how often housestaff notified primary care providers (PCPs) of admissions, whether notification prompted a visit, and whether PCP input impacted care, 210 medical inpatients were asked about their PCPs, and at discharge, housestaff completed a questionnaire on the patient's PCP, and whether he or she was contacted, came to the hospital, and influenced care. Of 105 patients with a PCP, 74 were contacted and 26 visited their patients. The PCPs spoken with personally more often made hospital visits than those contacted only by message (p < 0.0001). PCP input frequently contributed to patient care by providing continuity, clarifying history/diagnosis, managing chronic problems, and elucidating psychosocial/cultural factors. Having a PCP did not influence length of stay or readmission rates.