Psychiatrist. Born in Niederweningen, Canton Zurich. Graduated from the University of Zurich with a medical degree. Moved to the US in 1892. Took up positions as a psychiatrist at various universities and hospitals before being appointed to a professorship at Johns Hopkins University School of Medicine in 1908 and psychiatrist-in-chief at the hospital there in 1909. He trained two generations of psychiatrists and was very influential in American psychiatry in the first half of the 20th century, although his ideas were later disputed.