The authors investigated the potential of various time series models to aid in the prediction of platelet utilization patterns at the authors' institution. During a seven-week feasibility study, prediction accuracy of time series models was slightly inferior to that of an experienced platelet transfusion coordinator. The models that adjusted for day-of-the-week variability were superior to simpler models in a prospective evaluation over a three-month period. Conversion to a time series model for platelet utilization prediction has resulted in significant savings in personnel costs for management of platelet concentrate inventory in the blood bank. Outdate rates have been lower than those achieved by the platelet transfusion coordinator, with no sacrifice in availability occurring during the evaluation period.