The Internet has taken globalization of the marketplace from hyperbole to present-day reality. In this marketplace, information technology can be used to create and sustain market share. One such technology is the extranet. Extranets are increasingly being used to add value through business-to-business information sharing and transaction handling in a secure environment. Yet there is limited research into perceptions of service quality in Web-based Internet environments such as extranets. In this chapter we relate the literature on services and service quality to the developing literature on extranets. Five dimensions of service quality from the physical world are applied to the virtual world of commerce. It is concluded that dimensions of quality in human-to-human interactions may also apply to human-to-computer interactions, but that the factors which contribute to each dimension may differ.