Jan D. Sinnott, PHD, is a Professor of Psychology at Towson University in Baltimore, MD, and a Licensed Psychologist. She specializes in Lifespan Positive Development and the applications of existential, transpersonal, mind-body and positive psychology to adult growth and development. After completing a Postdoc at the National Institute on Aging, she developed her theory of complex problem-solving in adulthood, termed Complex Postformal Thought. She has authored or co-authored over 100 scholarly and applied books and publications. Her research team is currently studying Complex Problem-solving, Concepts of the Self, Intelligence, Mindfulness, and Satisfaction in Intimate Relationships. Her recent books include: Positive Psychology: Advances in Understanding Adult Motivation (2013, Springer) and Adult Development: Cognitive Aspects of Thriving Close Relationships (2014, Oxford University Press).