The Handbook of Psychology Concepts is handbook that provides brief and standard definitions and short notes on many of the concepts that are frequently used in modern psychology and other behavioural sciences, such as sociology and anthropology. The author is currently a senior lecturer at the Department of Sociology and Anthropology at The University of Benin, Benin City, Nigeria. He was the Hon. Commissioner for Education and Health in Delta State Nigeria, 1994 -1997.