Previous reports of variations in outcomes among neonatal intensive care units (NICUs) examined only specific subpopulations of interest (eg, very low birth weight [VLBW] infants /=stage 3 retinopathy of prematurity (ROP; 11%); >/=grade 3 intraventricular hemorrhage (IVH; 10%); nosocomial infection (22%); necrotizing enterocolitis (NEC; 7%). Sixty-nine percent of VLBW infants survived without major morbidity (>/=grade 3 IVH, chronic lung disease, NEC, >/=grade 3 ROP). The mean duration of NICU stay was 19 days. Forty-seven percent of infants were discharged from the hospital, and 43% were retrotransferred to a community facility before discharge home. Significant variation in practices and outcomes were observed in all aspects of NICU care.This study provides population-based information about NICU outcomes. Significant variation in NICU practices and outcomes was observed despite Canada's universal health insurance system. This national database provides valuable information for planning research, allocating resources, designing health and public policy, and serving as a basis for longitudinal studies of NICU care in Canada.