Background: In the United Kingdom, The Health and Occupation Reporting network (THOR) collects incidence data on work-related illness. THOR data show that the health and social work sector generates a high proportion of case reports. This study analyses the most recent data for the health and social work sector, from 2002 to 2003. Methods: Cases returned to the Occupational Physicians Reporting Activity (OPRA) scheme and three other specialist schemes (Surveillance of Occupational Stress and Mental Illness, Musculoskeletal Occupational Surveillance Scheme and occupational skin surveillance) were analysed. Estimates of incidence rates for stress-related illness, musculoskeletal disorders and skin disease were calculated using two denominators. Results: In this period, 23% (11 016/47 437) of all estimated cases in THOR were in health and social work sector employees. In OPRA, in the health and social work sector, annual average incidence rates per 100 000 calculated using Labour Force Survey (LFS) data as the denominator were 51.2 for mental illness, 35.9 for musculoskeletal disorders and 10.4 for skin disease; using McDonald's data as the denominator the corresponding rates were 119.5, 83.7 and 24.3. In the specialist THOR schemes, annual average incidence rates per 100 000 using LFS data as the denominator were 18.4 (mental illness), 6.1 (musculoskeletal disorders) and 15.3 (skin disease). Conclusions: Our results highlight the importance of collecting information on incident cases and denominators, to allow calculation of occupational disease rates. The higher incidence of mental illness (compared with musculoskeletal and skin disorders) in this employment sector merits further investigation. © The Author 2005. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved.