Internet trading is an irresistible business activity, which nevertheless is constrained by unresolved security issues. With e-tailers like amazon.com having a storefront for auction and the two largest traditional auction houses in the world, Christie’s and Sotheby’s, operating online auctions too; online auction systems are now playing an increasingly important role in e-commerce. However, online auction fraud has been reported in several high profile cases; this chapter offers some solutions for problems identified in online auction trading; which is largely unregulated and in which small auction sites have very little security. A secure architecture for online auction systems will greatly reduce the problems. The discussion herein is restricted to those factors that are deemed critical for ensuring that consumers gain the confidence required to participate in online auctions, and hence a broader spectrum of businesses are able to invest in integrating online auction systems into their commercial operations.