This chapter documents some of the links between e-business and knowledge management systems that might be explored in future empirical research. The research propositions in this chapter illustrate the need for a contingent approach to knowledge management systems that are to support e-business. Knowledge management systems successfully supporting and improving e-business performance have to satisfy several requirements. First, they have to support the chosen e-business model(s). Second, they have to cause improvements through redesign of e-business processes. Furthermore, more advanced stage of knowledge management technology in terms of codification strategy will be more powerful and successful. These are some of the research propositions presented in this chapter, which represents a rich knowledge base for future empirical studies. The main objective of a knowledge management system (KMS) is to support the creation, transfer, and application of knowledge in organizations (Feng et al., 2005). Electronic business (e-business) is marketing, buying, selling, delivering, servicing, and paying for products, services, and information across networks linking an enterprise and its prospects, customers, agents, suppliers, competitors, allies, and complementors (Weill & Vitale, 2002). Several researchers emphasize the important role of knowledge management systems in e-business (e.g., El Sawy, 2001; Fahey et al., 2001; Holsapple & Singh, 2000; Malhotra, 2000, 2002; Plessis & Boon, 2004; Singh et al., 2004; Tsai et al., 2005). Garud and Kumaraswany (2005) argue that knowledge has emerged as a strategically significant resource for the firm. Accordingly, knowledge creation and transfer becomes a key factor to gain and sustain a competitive advantage (Sambamurthy & Subramani, 2005). E-business processes can create additional customer value through knowledge creation with customers (Kodama, 2005).