Since the 1990s, the World Wide Web has brought about innumerable changes to the ways enterprises do business. Electronic commerce is emerging as one of the most important applications on the Internet. The use of agents in e-commerce is a new research area. Agents can provide effective, fast, and cheap ways to make deals and execute transactions in cyberspace. Abstract representations of value have been developed from metal, paper notes, and bank checks to savings cards, credit cards, and now electronic forms. This chapter presents a brief survey of existing different types of payment systems and focuses on mobile agent-based computing trends in e-commerce. By combining software agent technology with cryptographic techniques, an agent-based e-payment scheme built for the SAFER e-commerce architecture is proposed, which is aimed to provide a flexible and secure financial infrastructure for Internet commerce.