This volume is the result of over 20 years of psychological research by the author. It argues that those with high self-efficacy expectancies (the belief that one can achieve what one sets out to achieve) are healthier, more effective, and generally more successful than those with low self-efficacy expectancies. After a discussion of what self-efficacy is and where it comes from, the text discusses how belief in one's abilities affects developmental, mental functioning, and health; as well as its applications to the areas of psychopathology, athletics, business, and international issues.