The Temperament Discovery System features the Keirsey Temperament Sorter II and personality descriptions based on the book, "Please Understand Me II". Both were written Dr. David Keirsey, a clinical psycologist who worked in public schools for 20 years, and then spent 11 years training therapists and pathologists at California State University, Fullerton, in the art of changing dysfunctional behavior in children and adults.
