The author reviews the contributions of those individuals and major academic and professional organizations responsible for the development of the modern concepts of the premedical education of a physician. The late 19th century gave rise to scientifically-based medical education in U.S. medical education. It followed that this new emphasis, in medical schools, on laboratory investigation of disease processes demanded a sound introduction to the natural sciences by those who would be candidates for this type of challenging education. Starting with a vocal few, the message gradually was received throughout the country that a properly schooled physician must have the equivalent of a broad baccalaureate education in the natural sciences as well as in the traditional humanities. This essential was recognized by a small nucleus of individuals responsible for the creation of The Johns Hopkins University in 1876 and its school of medicine in 1893; the group was led by the university's first president, Daniel Coit GILMAN: Almost simultaneously other established academic institutions incorporated similar changes and a new era began.