Hans Selye is the father of stress research. His view of stress as a biological reaction at first provoked controversy. Due to Selye’s tireless pursuit of his experiments and his skill in communicating his results as much to the general public as to the scientific world, he eventually achieved general acceptance of his views. Selye’s work in his laboratory at the Université de Montréal contributed greatly to enlarging our understanding of the causes of illnesses, particularly those of the heart, and to the development of knowledge in his speciality, endocrinology.