This report presents the results of our self-initiated audit of the efficiency of operations at the St. Louis Processing and Distribution Center (P&DC) in St. Louis, MO (Project Number 22-112). We conducted this audit to provide U.S. Postal Service management with timely information on operational risks at this P&DC. We judgmentally selected the St. Louis P&DC based on a review of overtime; penalty overtime; late, extra, and cancelled trips by Postal Vehicle Service (PVS) and Highway Contract Route (HCR) drivers; and overall scanning performance. The St. Louis P&DC is in the Midwest Division, it processes letters and flats, and it services multiple 3-digit ZIP Codes in urban and rural communities (see Table 1).