Grenness has spent most of his career as a Professor at the University of Oslo, and has been active in many aspects of psychology, including philosophical psychology, behavioural analysis, organisational psychology and organisational studies.
Physical therapy | Reichian therapy | Therapy? | Radiation therapy | American Art Therapy Association | therapy | Therapy | Respiratory therapy | Oral rehydration therapy | Intravenous therapy | Gestalt therapy | Electroconvulsive therapy | Anti-social behaviour | American Physical Therapy Association | shock therapy | physical therapy | Beyond Therapy | art therapy | anti-social behaviour | Wilderness therapy | Whale surfacing behaviour | shock therapy (economics) | Physical Therapy | Occupational therapy | occupational therapy | National Association for Research & Therapy of Homosexuality | Human Behaviour | Feeling Good: The New Mood Therapy | Conversion therapy | Cognitive behavioral therapy |
During this time he also participated in an intensive training in Behaviour Therapy with Joseph Wolpe at the Eastern Psychiatric Institute, in Philadelphia, Pennsylvania, as well as studied Autogenic Training with Wolfgang Luth in Montreal, Canada.