Human umbilical cord and placental blood is a rich source of hematopoietic stem cells that can be used to reconstitute hematopoiesis after intensive myeloablative therapy. Therefore, it has become necessary to develop techniques for (i) collecting large volumes of umbilical cord aseptically, (ii) optimizing the yield of viable cells after cryopreservation and thawing, and (iii) minimizing the risk of maternal T-cell contamination. Our protocol for the collection, cryopreservation, storage, and transport of human umbilical cord and placental blood is described in detail.