Campbell has over 20 years’ experience working with couples, individuals and groups. He is a Registered Psychologist (AHPRA), and Certified Gottman Therapist (CGT) through the Gottman Institute based in Seattle, USA. He is a Member of the Australian Psychological Society (MAPS) and a Graduate of the Australian Institute of Company Directors (GAICD).

An interest in the dynamics of relationships has been a focus throughout his career as a Psychologist, whether in leadership development or in couples and marriage. Interest in the field of Positive Psychology led him to the work of John Gottman and his significant contribution to the scientific study of health and well-being in couples and family relationships.

His career has progressed from opera singer, English as a foreign language teacher (EFL), then Psychologist. From 2003 to 2013 he worked extensively as a consultant in organisations in Leadership Development. From 2009 he founded Positive Mind, a private psychology practice in Southern Highlands, NSW. He served in a voluntary capacity as a Director on the Board of Harbison, a large regional aged care facility, from 2011 to 2021, including as Deputy Chair.