Dr. Jean Marie Twenge is an American psychologist researching generational differences, including in life goals, work values, and speed of development. She is a professor of psychology at San Diego State University, consultant, public speaker and author. Dr. Twenge has examined generational differences in work attitudes, developmental speed, sexual behavior, life goals and religious commitment.

Jean is also known for her books Social Psychology (with David Myers), Generation Me (2006, updated 2014), iGen (2017) and The Narcissism Epidemic (2009, co-authored with W. Keith Campbell). She has also authored numerous research papers and articles.