The widespread recognition of the success of liver transplantation as a tre
atment for most types of acute and chronic liver failure has led to increas
ed referrals for transplantation in the setting of a relatively fixed suppl
y of cadaver donor organs. These events have led to a marked lengthening of
the waiting time for liver transplantation, resulting in increased deaths
of those on the waiting list and sicker patients undergoing transplantation
. Nearly 5000 liver transplantations were performed in the United States in
2000, while the waiting list grew to over 17,000 patients. The mounting di
sparity between the number of liver transplant candidates and the limited s
upply of donor organs has led to reassessment of the selection and listing
criteria for liver transplantation, as well as revision of organ allocation
and distribution policies for cadaver livers. The development of minimal l
isting criteria for patients with chronic liver disease based on a specific
definition for decompensation of cirrhosis has facilitated the more unifor
m listing of patients at individual centres across the United States. The U
nited Network for Organ Sharing, under pressure from transplant professiona
ls, patient advocacy groups and the federal government, has continuously re
vised allocation and distribution policies based on the ethical principles
of justice for the individual patient versus optimal utility of the limited
organ supply available annually. Beginning in 2002, it is likely that the
Model for End-stage Liver Disease (MELD) score will be implemented to deter
mine disease severity and direct donor organs to the sickest patients rathe
r than to those with the longest waiting times.