Hans Popper , THE founder and reigning monarch of modern hepatology, died on May 6, 1988. He was a man of colossal intellect, boundless energy and encyclopedic knowledge who dominated the field of liver disease for nearly half a century. His fertile imagination and intuition initiated or nurtured many of the field’s major scientific advances, and his contributions encompassed all aspects of the liver in health and disease. Investigators all over the world sought his critical judgment because the Popper imprimatur, if granted, conferred scientific credibility to new findings and concepts. As an inspiring and stimulating role model, he endowed countless students, fellows and coworkers with the intellectual curiosity from which sprang new and, at times, unorthodox discoveries. Under the leadership of this grand master, hepatology developed from a predominantly descriptive discipline to a science based on quantitative assessment of function and structure. As we eulogize Hans Popper, let us ponder his roots and his exceptional human and professional dimensions.