Using an electronic shelf-reading system a cost-benefit analysis was conducted of an inventory/shelf-reading project in a medium-sized academic library. Analyses include time spent, cataloging discrepancies, books found with active statuses, mis-shelving rate and distance, and subsequent use of found books. Correctly re-shelving "missing" materials was found to be more cost-effective and service oriented than repurchase. (Contains 8 tables, 2 figures, and 2 graphs.)