Our objective was to determine what family physicians need in their doctor's bag for urgent and non-urgent house calls. In a prospective survey, family physicians completed a structured report form after consecutive house calls, recording what equipment they needed for each. Thirteen doctors from two urban practices, making a total of 111 house calls, took part. Frequency of reported need of diagnostic equipment, therapeutic agents and administrative supplies was measured. Items required more than 70% of the time were: stethoscope; sphygmomanometer; patient's medical chart; and prescription pad. All other items were required in less than 30% of house calls. We conclude that doctors should carry a stethoscope, sphygmomanometer and prescription pad with them at all times; the patient's medical chart is also essential. Additional equipment should be accessible as prepared kits and taken as needed, depending on the particular patient's problem.