John brings a rich and multifaceted background to his clinical work. He began his adulthood as a priest, did an M.Sc. in Chemistry and was Principal of St. Jerome’s High School in Kitchener-Waterloo. After leaving the clergy he was a professor at the University of Waterloo in Psychology for 26 years before taking early retirement to work in full-time private practice. This diverse life experience shapes his approach to therapy.
Much of Dr. Theis’ training in family therapy was done over many years in Italy. He remains a wannabe Italian.
Dr. Theis is calm, insightful and untroubled by complexity and chaos, especially in families. He anchors people with kindness and solidity during life's storms.
He values treating each client as unique and tailoring the therapeutic approach to their needs.
Dr. Theis draws from several approaches:
Humanistic & Existential Therapy
Family Systems
Cognitive Behavioural Therapy
Interpersonal Therapy
Integrative & Client-Centered
He works with adult individuals, couples and families experiencing
Relationship issues
Anxiety
Depression
Life transitions
Fathers and sons
Personal growth/reflection
Grief and aging
Clinical supervision and consultation
Dr. Theis offers virtual therapy sessions for adult individual, couples and families. He does not offer free consultations but encourages prospective clients to review therapist profiles and reach out with any questions prior to booking.
Clinical Psychologist in Ontario
Certified in Relationship and Family Therapy
University professor in Psychology (retired in 1996)
In private practice since 1996
Based in Guelph since 2003
Email: [email protected]
Phone: 519-836-1277
Virtual sessions available | Now accepting clients
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