​​​(905) 527-2507

Dr. Holshausen is a Registered Clinical Psychologist. She specializes in mood and anxiety disorders, posttraumatic stress disorder/complex trauma, and emotion regulation difficulties. Dr. Holshausen also works as a staff psychologist and Research Director of the Community Psychiatry Clinic at St. Joseph’s Healthcare Hamilton.


Dr. Katherine Holshausen received her Ph.D. in Clinical Psychology from Queen’s University in 2017. She completed her residency at St. Joseph’s Healthcare Hamilton, where she provided assessment and treatment services to adults, specializing in mood, psychosis, and complicated trauma presentations. Dr. Holshausen currently works as a staff psychologist and Research Director of the Community Psychiatry Clinic at St. Joseph’s Healthcare Hamilton. In this position Dr. Holshausen trains students and junior staff, provides assessment and treatment to clients, and overseas research projects across several services in the hospital.

Dr. Holshausen offers assessment and treatment services for adults with diverse presenting needs including mood, anxiety, insomnia, relationships difficulties, trauma, self-esteem, and difficulties with experiencing and managing emotions (e.g., sadness, anger, shame, guilt). Dr. Holshausen aims to provide a client-centered approach that relies on evidence-based practices coupled with compassion and humour. Dr. Holshausen is trained in a number of therapy approaches including cognitive-behavioural therapy, cognitive processing therapy (for PTSD), prolonged exposure (for PTSD), motivational interviewing, dialectical behaviour therapy, and mindfulness.


Ph.D., C.Psych. 

Dr. Katherine Holshausen