OBJECTIVE To determine whether vitamin A supplementation at birth could reduce infant morbidity and mortality. STUDY DESIGN We conducted a placebo-controlled trial among 2067 Indonesian neonates who received either 52 micromol (50,000 IU) orally administered vitamin A or placebo on the first day of life. Infants were followed up at 1 year to determine the impact of this intervention on infant mortality. A subgroup (n = 470) was also examined at 4 and 6 months of age to examine the impact on morbidity. RESULTS Vital status was confirmed in 89% of infants in both groups at 1 year. There were 19 deaths in the control group and 7 in the vitamin A group (relative risk = 0.36; 95% confidence interval = 0.16, 0.87). The impact was stronger among boys, infants of normal compared with low birth weight, and those of greater ponderal index. Among infants examined at 4 months of age, the 1-week period prevalence of common morbidities was similar for vitamin A and control infants. However, during this same 4-month period, 73% and 51% more control infants were brought for medical treatment for cough (p = 0.008) and fever (p = 0.063), respectively. CONCLUSIONS Neonatal vitamin A supplementation may reduce the infant mortality rate and the prevalence of severe respiratory infection among young infants.