Clinical, economic, and epidemiologic data were used to compare the costs of conventional inpatient care of osteomyelitis with the costs of early-discharge treatment using a once-daily parenteral antibiotic at home. Estimated expenses included inpatient medical care, outpatient visits, supplies, child care, home care, transportation, and lost productivity. Early-discharge treatment was associated with lower medical direct, non-medical direct, and indirect expenses than conventional inpatient treatment. Estimated savings per patient ranged from $510 to $22,232 (demonstrating the wide differences in estimated savings when different sources of data on hospital costs are used). These savings are due to large decreases in inpatient costs, which are partially offset by increased outpatient costs. However, because outpatient costs are more often borne by patients than are inpatient costs, early-discharge treatment could be more expensive from the patient's perspective, despite its savings for the hospital and for society as a whole.