Objective: The bidirectional Glenn procedure is a well-established procedure performed as part of the single-ventricle palliation pathway. Numerous studies have highlighted the potential benefits of an "early" BDG procedure. The ideal age to perform the BDG procedure, however, remains uncertain. We report our experience with the BDG procedure in patients younger than 3 months. Methods: One hundred sixty-nine consecutive patients from 1998 to 2007 undergoing the BDG procedure were divided into 2 groups: younger than 3 months (n = 20) and older than 3 months. The groups were compared for 26 variables. All data were analyzed with Kaplan-Meier survival analysis and the Cox proportional hazard regression test to assess the probability of survival after the BDG procedure in both groups. A stepwise regression analysis was performed for identification of independent factors for postoperative oxygen saturation at hospital discharge. Results: The groups were comparable, with an equal distribution of patients with right-sided or left-sided single-ventricle anatomy. Although intensive care unit length of stay, ventilation time, and hospital length of stay were longer in the younger group, room air oxygen saturations at discharge, both early and late mortality, and time to the Fontan procedure were similar between groups. The independent variables found for death after the BDG procedure were preoperative mean pulmonary artery pressure, atrioventricular valve regurgitation, and postoperative oxygen saturations at hospital discharge. Survival in patients with hypoplastic left heart syndrome was comparable between groups after 5 years of follow-up. Conclusion: The BDG procedure is feasible and safe in patients as young as 2 months of age, with early and late mortality equivalent to that seen in older patients.