Alfred Adler ( AD-lər, German: [ˈalfʁeːt ˈʔaːdlɐ]; 7 February 1870 – 28 May 1937) was an Austrian medical doctor, psychotherapist, and founder of the school of individual psychology. His emphasis on the importance of feelings of belonging, family constellation and birth order set him apart from Freud and other members of the Vienna Circle. He proposed that contributing to others (Social Interest or Gemeinschaftsgefuhl) was how the individual feels a sense of worth and belonging in the family and society. His earlier work focused on inferiority, the inferiority complex, an isolating element which plays a key role in personality development. Alfred Adler considered a human being as an individual whole, and therefore he called his psychology "Individual Psychology" (Orgler 1976).

Adler was the first to emphasize the importance of the social element in the re-adjustment process of the individual and to carry psychiatry into the community. A Review of General Psychology survey, published in 2002, ranked Adler as the 67th most eminent psychologist of the 20th century.