To determine safety and cost-effectiveness of 24-hour discharge in selected mothers and newborns. Women delivering at University Hospital (the University of Alabama at Birmingham) were screened to determine their eligibility for 24-hour discharge. Mothers were eligible if they had no medical problems and no history of substance abuse, had an uncomplicated vaginal delivery and postpartum course, were 12 or more hours after postpartum bilateral tubal ligation, and had reached 24 hours after delivery by 6:00 pm on the day of discharge. Newborns were eligible if they were term (37 weeks or greater), weighed 2500 g or greater, and had a normal examination at 24 hours of age. At 48 hours after delivery, each mother and infant pair was examined by a home health nurse. Telephone consultations with a staff physician were noted and outcomes were entered into a data base linked to hospital financial data. Of 5621 deliveries from October 1, 1993 to September 30, 1995, 972 mothers (17%) and 856 (15%) newborns were discharged at 24 hours. One mother was lost to follow-up after discharge. Nine-hundred fifty-six of 971 mothers (98.5%) had a normal examination at the home visit. Fifteen of 971 mothers (1.5%) had problems that required obstetrician telephone consultation. Seven mothers (0.7%) required a physician visit; two of these women were read-mitted for treatment of an infection. Seven-hundred ninety-five of 856 (93%) newborns had a normal examination. Sixty-one newborns (7%) had problems that required pediatrician telephone consultation, primarily for jaundice, infant care questions, and a cardiac murmur. Twelve infants (1.4%) required a pediatric clinic visit. No infant was read-mitted to the hospital. Net cost savings to our hospital for 24-hour discharge in these selected patients was $506,139 during a 2-year period. In a selected, low-risk, low-income population, mother-infant discharge 24 hours after delivery with a home follow-up visit is safe and cost-effective.