This article presents the results of an empirical study recently performed in e-commerce organizations. The purpose of this empirical study was to figure out the usage of electronic product catalogs and especially their systems used for product classification, such as UNSPSC or eCl@ss. The study was performed in August and September of 2004 with the help of a survey that was sent out to a selection of those product suppliers and manufacturers where product catalogs are crucial for business. This article first presents the necessary fundamentals needed for understanding the results of the survey. Then, it presents the results and identifies problematic areas that should be improved. In addition, it gives some advice for e-commerce organizations, standardization committees, and further research activities to foster the usage of modern classification systems in electronic product catalogs.