We investigated the effect of the expanded criteria donor (ECD) label on (i) recovery of kidneys and (ii) acceptance for transplantation given recovery. An ECD is age > or = 60, or age 50-59 with > or = 2 of 3 specified comorbidities. Using data from the Scientific Registry of Transplant Recipients from 1999 to 2005, we modeled recovery rates through linear regression and transplantation probabilities via logistic regression, focusing on organs from donors just-younger versus just-older than the ECD age thresholds. We split the sample at July 1, 2002 to determine how decisions changed at the approximate time of implementation of the ECD definition. Before July 2002, the number of recovered kidneys with 0-1 comorbidities dropped at age 60, but transplantation probabilities given recovery did not. After July 2002, the number of recovered kidneys with 0-1 comorbidities rose at age 60, but transplantation probabilities contingent on recovery declined. No similar trends were observed at donor age 50 among donors with > or = 2 comorbidities. Overall, implementation of the ECD definition coincided with a reversal of an apparent reluctance to recover kidneys from donors over age 59, but increased selectiveness on the part of surgeons/centers with respect to these kidneys.