This chapter examines the convergence of two of today’s most pressing security challenges: international terrorism; and, cyberattack. Drawing on both published research and a survey of the global research community, the chapter shows that, whilst the majority opinion is that cyberterrorism is a (current or potential) significant threat, there are also some strong dissenting voices. It then addresses questions of response, focusing particularly on methods for improving cyber defense and the introduction of new laws, and argues that partnership between the private and public sectors and members of the international community is necessary for such responses to be effective.