Stem cells for allogeneic transplant are traditionally obtained from one of three sources: bone marrow (1), peripheral blood stem cells mobilized by provision of the growth factor GCSF (2), or umbilical cord blood (3). Each source has specific advantages and disadvantages. The desired source of stem cells for allogeneic transplant is a matched sibling donor. However, if that is not feasible, a matched unrelated donor can be sought through the National Marrow Donor Program (NMDP). The National Marrow Donor Program (NMDP) in Minneapolis, Minnesota, was established in 1986 to facilitate the search for, and procurement of, HLA-matched marrow from volunteer, unrelated marrow donors for patients with life-threatening diseases curable by SCT (7). The NMDP network consists of 99 donor centers, 108 collection centers, 150 transplant centers and a Coordinating Center in Minneapolis. As of June 29, 2003, the NMDP had a registry of 5,032,382 volunteer marrow donors and 28,574 cord blood units stored, and had facilitated 13,213 unrelated marrow transplants (marrow, PBSC and cord blood) worldwide. Over 600,000 donors in the NMDP Registry are contributed by European registries, which are affiliated with the NMDP. In addition, approximately 1 million donors are available by searching NMDP International Cooperative Registries in Europe, South America, and Asia. On average, searching patients have a 75% chance of finding a match within the NMDP, with a median time from search to transplant of less than 6 months. Vanderbilt University Medical Center is a NMDP approved aphaeresis center, collection center and transplant center and adheres to the policies and procedures of the NMDP as outlined in The 18th Edition of the NMDP Standards (effective since September 13th, 2002, implemented February 10th, 2003).