This chapter investigates the concept of the greater the governmental need the better the justification for intruding upon baseline rights and liberties. As an example, it explains that a legislature may have license to pursue a compelling need by means claimed necessary even while deviating from strict protection of a constitutional right. It explains how necessity can enhance or diminish the scope of pre–existing powers of a defined government office, such as granting a president confronting a military emergency with wide discretionary latitude to act with enhanced executive powers without having to claim new ones. The chapter also assesses how channeling executive discretion into a judicial doctrine of “exigency” enhances the scope of government action in relation to a protected right. It focuses on counterterrorism surveillance practices, which argues that the existence of exigency doctrines provides ways to normalize necessity in everyday governing practice.