The Keirsey Temperament Sorter?-II is the most widely used personality instrument in the world. It is a powerful 70 question personality instrument that helps individuals discover their personality type. The Sorter is based on Keirsey Temperament Theory?, published in the best selling books, Please Understand Me? and Please Understand Me II, by Dr. David Keirsey. This App keeps your information private and can save your answers for later. Note: The Kersey Sorter uses "N" for iNtuitive as "I" is allocated to Introvert.