The Individual Psychology of Alfred Adler provides a rich theoretical foundation for what has developed into Adlerian psychotherapy. This chapter defines the basic tenets of Adler’s theory of personality and therapy. Adler’s theory is grounded on the idea that childhood experiences are crucial to the psychological development, and that children, who are by nature in an inferior position to parents and other adults, strive to achieve some sense of superiority. Adler ’s work represents a psychological theory that acknowledges the influence of social factors on the personality. In efforts toward understanding the lifestyle, Adler viewed humans’ unique approaches to life through the lenses of the life tasks. These tasks included: the work task, the social task, and the sexual task. Adler believed that encouragement, the act of promoting courage within someone else, was the cornerstone of therapy and could inspire clients toward growth, healthy adaptation, and functioning in life.