In a retrospective study we found that 19 of 80 women with systemic lupus erythematosus had atypical cervical smears as compared to only 9 of 80 age-matched women without the disease. This increased incidence occurred mainly among women receiving cytotoxic drugs. Cervical atypia in women with lupus was not morphologically different from cervical atypia in general. Possible mechanisms responsible for the increased incidence are discussed. It is concluded that women with lupus who receive chemotherapy should have cervical smears taken regularly.