This chapter assesses sanctions as a (global) security governance tool. Law is an obvious tool for ‘security governance’, and ‘sanctions’ are an inextricable element of law. The chapter begins by discussing the meaning of sanctions and (global) security. It then traces the historical trajectory in the use of collective and unilateral sanctions in the service of security. It argues that global security is nothing but national security projected onto the international plane. When a hegemonic concept of security—that is to say, of the existential threats ‘we’ need to protect against—is imposed and accepted, and for as long as it is accepted, collective sanctions rule supreme and can be particularly effective. When there is fragmentation and antagonism as to what the threats are, when there is no hegemonic national security accepted as synonymous to international security, there is a return to unilateral sanctions and a concomitant sidelining of collective security mechanisms.