Some studies have demonstrated increased risk of different cancers among female nurses. A review of relevant papers was made to assess whether the increase is caused by occupational exposures or other factors. A computerized literature search on combinations of the keywords 'nurses', 'occupation', 'hazards', 'cancer' and 'mortality' and related articles was performed. A total of 30 reports were identified from 19 independent studies conducted between 1983 and 2001. The majority of the studies were registry studies, with limited data on employment history and confounding factors. In conclusion, knowledge about exposures and observed excesses of cancer risk give reason to suspect an occupational influence on breast cancer and leukaemia. The grouping together of nurses from different workplaces may camouflage real differences in risk. Future studies should collect information at the individual level about work history and personal risk factors.