Medical education is placed on a firm scientific foundation, and the teaching faculty, in its entirety, consists of specialists. The basic sciences of bacteriology, physiology and pathology are revolutionized and technology begins to transform medicine. Abraham Flexner’s report in 1920 completes the transformation by proposing broad reforms in graduate medical training. The result is the age of specialization during the first half of the 20th century. Rapid technological progress maximizes specialist prestige, emphasizes research skills and laboratory science at the expense of personal care and de-popularizes general practice as a career field. By the 1950s super-specialization occurs.