Abstract: A method and apparatus are provided for producing a catalog of items that are to be offered for sale. A computer system is employed wherein a catalog item number is assigned to the items that are to be listed in the catalog. Each unique item contains a unique catalog item number. A cataloging software program that is executed by the computer determines whether an inputted item has previously been assigned a catalog item number by comparing the inputted item against a plurality of items in a master item list. If a catalog item number has not previously been assigned to the inputted item, a new catalog item number is generated and assigned to the inputted item. However, if the cataloging system determines that the inputted item already exists in the master item list, the catalog item number assigned to the item in the master list is also assigned to the inputted items. Accordingly, all like items have the same catalog item number, whereas different items have different catalog item numbers.