The convergence of terrorism and cyberspace has tremendously changed the threat landscape in a way that reached an unmanageable complexity. Understanding new risks posed by cybererrorism constitutes a main concern for both national authorities and research communities. This chapter provides insights on the use of modeling and simulation to support decision-makers in understanding cyber risk scenarios at both operational and strategic layers. The overall objective is to stimulate a multidisciplinary research that bridges practice and theory by accounting for different perspectives and combination of quantitative tools to face the challenge of (cyber-) terrorism.