Abstract: [Correction Notice: An erratum for this article was reported in Vol 49(3) of Canadian Psychology/Psychologie canadienne (see record 2008-10897-013). Figure 1 on page 17 was incorrect. The correct figure is printed in the text.] Self-determination theory (SDT) differentiates motivation, with autonomous and controlled motivations constituting the key, broad distinction. Research has shown that autonomous motivation predicts persistence and adherence and is advantageous for effective performance, especially on complex or heuristic tasks that involve deep information processing or creativity. Autonomous motivation is also reliably related to psychological health. Considerable research has found interpersonal contexts that facilitate satisfaction of the basic psychological needs for competence, autonomy, and relatedness to enhance autonomous motivation, which comprises intrinsic motivation and well-internalized extrinsic motivation. SDT has been applied in varied cultures and in many life domains, and research is reviewed that has related autonomous and controlled motivation to education, parenting, work, health care, sport, and close relationships.