||This thesis consists of three studies on Buy-It-Now (BIN) auctions, which is an auction mechanism developed by electronic marketplace operators with an aim to reduce the negative effect of information asymmetry. At present, there are two formats of BIN auction, viz. the eBay format, and the Yahoo! format. Both formats provide bidders an opportunity to win the auction instantly at the outset of the auction when any bidder accepts the BIN price (PBIN) posted by the seller. The difference between these formats is, the BIN option will no longer be available and the auction will convert to an ascending auction for the eBay format when any bid above the reserve price is submitted, whereas the BIN option appears throughout the auction for the Yahoo! format. These three studies on BIN auctions are focused on the impact of this new auction mechanism on stakeholders of electronic marketplaces. In the first study, I investigate the impact of PBIN on the closing price of electronic auctions. A model is developed to explain how bidders and sellers use PBIN as a piece of information for better estimation of the number of active bidders in electronic auctions and the expected closing price of electronic auctions. Empirical data were collected from auction websites to support the model. The preliminary finding of this study was reported at the 39th Hawaii International Conference on System Sciences (HICSS) in January 2006 (Yoo, Ho and Tam, 2006). In the second study, I examine those factors affecting the decision of sellers on whether they would choose to use BIN auctions to auction their goods. I show that product types and culture are important factors, which affect the level of use of BIN auctions by sellers. I also observe that culture has a significant moderating effect on the effect of product types on the level of use of BIN auctions. The preliminary finding of this study was reported at the Pacific Asia Conference on Information Systems 2006 (Ho et al., 2006), and in the Journal of Global Information Management (JGIM) (Ho et al., 2007). The aim for the third study is to investigate factors leading to successful auction of items using BIN auction format in electronic marketplaces. A conception model is proposed to explain how reputation of sellers, product attributes, and BIN auction format affect bidders’ choice in participating in BIN auctions or not.