The United Network for Organ Sharing has mandated the national sharing of well-matched cadaveric kidneys with payback to the national pool. On March 6, 1995, the policy was extended to include sharing of cadaveric kidneys for which there is a recipient with a 0-HLA mismatch (0-MM). However, the beneficial effects of this policy have been questioned. To address these concerns, we analyzed the effects of this system on graft survival, cold ischemia time, and the transplantation of highly sensitized patients during the 0-MM era.