The American Society of Nephrology and the fellowship training program directors in conjunction with the National Board of Medical Examiners developed a comprehensive assessment of medical knowledge for nephrology fellows in-training. This in-training examination (ITE) consisted of 150 multiple-choice items covering 11 broad content areas in a blueprint similar to the American Board of Internal Medicine certifying examination for nephrology. Questions consisted of case vignettes to simulate real-life clinical experience. The first examination was given in April 2009 to 682 fellows and six training program directors. Examinees felt that the examination was well structured and relevant to their training experience Longitudinal performance on the examination will be helpful in allowing training programs to utilize results from content areas in identifying deficits in medical knowledge as well as assessing the results of any curriculum changes. Copyright © 2010 by the American Society of Nephrology.