This book is based on a Ph.D. dissertation written at University of Mississippi. It investigates the decision about the revelation of bidder information in online auctions. It makes a novel contribution to the literature by investigating the relationship between bidder information asymmetry and bidder experience level. Bidder information is a signal about the experience level of bidder. Bidder experience affects the strategic decisions of both buyers and sellers. Using data from 500 Egyptian antique auctions (a common value auction) and 500 laptop auctions (a private value auction), following main results are identified.First, in common value auctions, sellers earn higher average prices when they conceal bidder information. In private value auctions, sellers generate higher average prices when proportionally more inexperienced bidders are present, regardless of whether or not they reveal bidder information. Then, in common value auctions, late bidding is observed more frequently when bidder information is revealed. Late bidding is relatively less common in private value auctions than in the common value auctions, regardless of whether or not sellers reveal bidder information.