Injury rates of rotating shift workers were compared with rates for fixed shift workers. The health and safety records of 1,228 nurses were examined for information on sex, age, length of employment, marital status, and nature and frequency of on the job injuries during a 6 month period. Fixed shift nurses had a significantly different distribution of injuries in the 6 month period than the rotating shift nurses. Rotating shift nurses had an injury incidence of 23.3 per 100 man years of work compared to 18.0 for night shift nurses, 16.8 for day shift nurses, and 15.7 for afternoon shift nurses. The rotating shift nurses had significantly greater incidences of cuts, bruises, punctures and contusions, and crushings than fixed shift workers, and significantly fewer sprain and strain injuries. Fixed day and night shift workers did not differ in injury incidence. Differences in age, work experience, and marital status did not account for the differences in injury rates. The authors suggest that differences in injury rate across shifts may be due to shift schedule or to other associated variables.