The Internet has dramatically changed how people sell and buy goods. In recent years we have seen the emergence of electronic marketplaces that leverage information technology to create more efficient markets (e.g., online auctions) to bring together buyers and sellers with greater effectiveness at a massive scale. Despite the growing interest in and importance of such marketplaces, our understanding of how the design of the marketplace affects its use is still quite limited. This paper presents a detailed case study of a currently operational massive scale online auction marketplace. The main focus is to gain initial insights into the effects of the design of the marketplace. The results of the study point to several important considerations and implications not only for the design of online marketplaces but also for the design of large-scale websites where effective locating of information is key to user success. Keywords Electronic Marketplaces, Massive Scale Online Auctions, Onlin...