During the last ten years there has been a growth of Information Systems and related Internet technology. In recent years the Internet has grown from a solely military/academic network to one that can be used by business or individuals. In the years since the first World Wide Web (WWW) applications were developed, there has been an explosion in the global use of the Internet. With this growth has come an increasing usage of the medium by criminal and terrorist groups.This chapter will explain why and how cyber-terrorists attack these services. The aims of the chapter are to: describe the background of cyber-terrorism; describe what cyber-terrorism is; describe the vulnerabilities of electronic commerce to cyber-terrorism; discuss the future of electronic commerce and cyber-terrorism.