Don Richard Riso is a pioneering teacher, researcher and author in Enneagram studies. President of the Enneagram Personality Types, Inc. in New York City, and Founding Director of the International Enneagram Association, he holds a M.A. from Stanford University.
He is the most published writer in the field, and his books are now the standard references, especially Personality Types and Understanding the Enneagram. He has appeared on scores of radio and television programs and has taught the Enneagram internationally.