John Bowlby was a British psychologist perhaps best known for developing attachment theory. His research on attachment and child development left a lasting impression on psychology, education, child care and parenting. Researchers extended his research to develop clinical treatment techniques and prevention strategies. His work also influenced other eminent psychologists, including his colleague Mary Ainsworth who also made major contributions to attachment theory. Learn more about his early life, career, theories and influence on psychology in this biography of John Bowlby.