Dr. Theis came to the practice of therapy from quite a diversified background - he was a priest for ten years, a high school administrator and a university professor. Over his years as a university professor of Psychology, he also had a small private practice in therapy. He took early retirement from the university in 1996 and established a full-time therapeutic practice in Waterloo. He moved to Guelph in 2003 and has been in practice in this office since that time.