This chapter reviews existing scholarly and policy-oriented literature that addresses WMD terrorism in order to identify broader trends and assess the current WMD terrorism threat. It argues that the WMD terrorism literature has reached a kind of plateau in which the same speculative, unsubstantiated interpretations are constantly recycled. Most experts have concluded that WMD terrorism is not an imminent or catastrophic threat. Indeed, they often complain that unlikely “worst-case” scenarios have led to too much money being spent on consequence management and other poorly designed measures.