He was born and educated in England, and did his basic rheumatology training with Professor Eric Bywaters at the Royal Postgraduate Medical School in London. He has lived in the USA since 1972 and did additional training with Professor Daniel McCarty at the University of Chicago.

He was Chairman of the Division of Arthritis and Rheumatic Diseases at OHSU for 24 years (1976-2000). Dr. Bennett is a Board Chairman of the International Myopain Society, and a past President of the International Myopain Society American College of Rheumatology Western Region.

He and his colleagues developed the Fibromyalgia Impact Questionnaire (FIQ) in 1993; it is now the most widely used instrument for measuring disease activity in fibromyalgia patients.

He was first to report adult growth hormone (GH) deficiency in a subset of fibromyalgia patients in 1992 and has subsequently shown the benefits of GH replacement. He holds patents for the utilization of GH in fibromyalgia, chronic fatigue syndrome, rheumatoid arthritis and polymyalgia rheumatica.

His bench research involves the molecular characterization of cell surface DNA receptors (US Patent # 5,965,520). He has published over 400 articles and book chapters. He has been on the editorial boards of Pain, Arthritis & Rheumatism; Geriatrics; the Journal of Musculoskeletal Pain; the Journal of Functional Syndromes.