Adler, Alfred (1870–1937), an Austrian psychologist, founder of the school of individual psychology. Adler believed that humans strive throughout their lives to achieve contentment and fulfillment, in an attempt to compensate for strong feelings of inferiority developed in childhood. Most persons are able to compensate satisfactorily; those who are unsuccessful develop neuroses. Adler explained his theories in The Theory and Practice of Individual Psychology (1918), Understanding Human Nature (1927). and Pattern of Life (1930).

Adler was born in Vienna. He received a degree in medicine from the University of Vienna in 1895. In 1902 Adler became associated with Sigmund Freud, founder of psychoanalysis. Rejecting Freud's emphasis upon sex as a significant motive behind human behavior, he broke with him in 1911. Adler spent much of his time after 1925 lecturing in the United States.