While cautious criteria for selection of living kidney donors are credited for favorable outcomes, recent practice changes may include acceptance of less than ideal donors. To characterize trends in donor acceptance, the Renal and Lung Living Donors Evaluation (RELIVE) Study evaluated 8,951 kidney donors who donated between 1963 and 2007 at three major U.S. transplant centers. Over the study interval, there was an increase in the percentage of donors >40 years old from 38% to 51%; donors >60 years varied between 1% and 4%. The proportion of donors with obesity increased from 8% to 26% and with glucose intolerance from 9% to 25%. The percentage of hypertensive donors was consistent (5-8%). Accepted donors ≥60 years old were more likely to have obesity, glucose intolerance, and/or hypertension compared to younger donors (p<0.0001). Our results demonstrate important trends in acceptance of older and more obese donors. The fraction of older donors accepted with glucose intolerance or hypertension remains small and for the majority includes mild elevations in glucose or blood pressure that were previously classified as within normal limits. The Renal and Lung Living Donors Evaluation (RELIVE) Study reports explosive growth in numbers of living kidney donors, particularly those between 41-60 years old; a 25% increase in the percentage of patients with obesity or glucose intolerance; steady, low rates of hypertension; and trends to higher median values for BMI, fasting glucose, and systolic blood pressure over five decades. © Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.