We describe the procedures employed for transporting bone marrow to and from a central facility. Marrow has been harvested from 80 patients with neuroblastoma, at 16 centers which are geographically dispersed throughout North America. Marrow from the outside transplant centers was packed on wet ice or cold packs in insulated containers, and transported by commercial carriers or chartered aircraft to the central processing laboratory. Post processed marrows were frozen in liquid nitrogen and returned by commercial carrier to the referring institution. In comparing transported with non-transported but similarly treated marrows, no differences were found in any of the following parameters: (1) CFU-GM recovery, (2) fraction viable cells at thawing, or (3) time to engraftment in patients. We conclude the transportation of harvested marrows to a central purging facility is safe. Based on this experience, we propose a set of standards, which, if adhered to, will insure the continued safe processing, shipping, and storage of bone marrow in all centers so engaged.