He specialized in studying evolutionary theory and childhood development, and investigating the extent to which behaviour is inherited. He began his career as a teacher and was president of Clark University from 1889 until 1920. In 1887 Hall founded the American Journal of Psychology, and in 1892 he was appointed the first president of the American Psychological Association. A pioneer in the study of anomalistic psychology, Hall was a founding member of the American Society for Psychical Research, but resigned in 1890 and became an outspoken critic of parapsychology.