Umbilical cord blood has been recently used as a source of hematopoietic progenitor cells for transplantation of pediatric patients. This study was performed to evaluate the feasibility of a cord blood bank for unrelated transplant. When the umbilical cord was clamped within 20 seconds after delivery, it was possible to collect 86 +/- 25 ml of cord recipients with more than 2000 CFU-GM/kg; 53% of cord blood samples were found to contain enough CFU-GM for engraftment in 50-70 kg adult patients.