Adolph Meyer influenced Curt Richter from the time Richter became a graduate student in Psychology at Johns Hopkins in 1919 until Meyer retired in 1941. Meyer was on Richter’s thesis committee. After Richter received his degree, Meyer selected him to replace J.B. Watson. During the next 20 years, Meyer gave Richter strong support in terms of equipment, laboratory space for animal research, and opportunities to teach medical students, attend clinical rounds, and do clinical research. It is less well known that Meyer also mentored Richter’s scientific and professional development. Meyer’s mentoring was so successful that Richter adopted the major scientific ideas of Meyer, especially psychobiology, distrust of theory, and respect for experiment. Thus, Meyer’s ideas became the framework for Richter’s famous research program that produced his major discoveries of behavior exerting homeostatic controls, psychoendocrinology, and biological clocks.