 In 1937 La Barre was made a Sterling Fellow at Yale, and conducted field work in South America with the Aymara of Lake Titicaca region and the Uros of the Rio Desaguadero.In 1938 his first book, "The Peyote Cult", was published, and was immediately hailed as a classic, on the cutting edge of psychological anthropology.He was enabled by a Social Science Research Council Postdoctoral Fellowship to go to the Menninger Clinic in Topeka, Kansas in order to be trained in psychoanalysis, and from 1938 to 1939 he continued his research into the psychological depths of indigenous cultures at the clinic.