Trends in child care have affected the epidemiology of many infectious diseases. Although once considered rare Cryptosporidium is now recognized as a significant pathogen in child care settings. Although the major impact of cryptosporidiosis in child care settings is economic in terms of parental time lost from work due to a child's illness, the possibility of transmission to immunocompromised individuals and health effects of cryptosporidiosis underscore the significance of this pathogen. Our understanding of the epidemiology of cryptosporidiosis in child care settings is hampered by the lack of information from both cross-sectional and prospective studies. Such studies coupled with the use of newer diagnostic techniques and methods that are currently under development for identifying Cryptosporidium in environmental samples are sorely needed. Information is also needed on the effectiveness of prevention and control strategies. Although prevention strategies may be based on findings from broad based studies that do not focus on any one agent, differences in duration of excretion, rates of asymptomatic infection, availability of treatment and survival in the environment suggest that control strategies for specific pathogens should be evaluated.