The Occupational Physicians' Reporting Activity (OPRA) surveillance scheme for occupational physicians has now been in place for 4 years. During this period, an estimated 43,764 new cases of work-related disease have been reported. Musculoskeletal conditions make up nearly half (49%) of all cases; mental ill-health and skin disease account for 20% each, with respiratory conditions (8%) and hearing loss (5%) seen in lower proportions. Overall, eight of 42 diagnoses made up four-fifths of the new cases reported by occupational physicians. These were hand and arm disorders (8052 estimated cases), contact dermatitis (7104), disorders of the lumbar spine (6000), anxiety and depression (4788), work-related stress (3336), hearing loss (2100), elbow disorders (2040), and asthma (1680). Dermatitis and hearing loss were most frequent in manufacturing industries, lower back complaints in health care, and upper limb disorders in automotive manufacture. Psychiatric illnesses presented a different pattern, mainly affecting those in health, education and social service.