The Planning and Analysis Unit of the Lexington Police Department changed from rotating to permanent shift assignments. We report herein the results of patrol officers' responses to the Florida Sleep Questionnaire, the SCL-90 (a symptom checklist), and absentee data. Sleep quality and sleep hygiene improved after changing from rotating to permanent shifts. The SCL-90 demonstrated improved psychologic well-being. Further, absentee rates fell from 1400 hours during the 6 months preceding the shift change to 883 hours during the 6 months following the change. We review the literature concerning the effects of shift work on worker performance.