Maritime security, also known as non-military security, refers to a condition in which the maritime rights and interests of a State, recognised by the United Nations Convention on the Law of the Sea and other rules of international law, are free from harm, danger or attack. This chapter discusses seven acknowledged threats to maritime security in the exclusive economic zone (EEZ) and the international legal framework for addressing them. The seven threats are piracy and armed robbery against ships; terrorist acts involving shipping, offshore installations and other maritime interests; illicit trafficking in arms and weapons of mass destruction; illicit traffic in narcotic drugs and psychotropic substances; smuggling and trafficking of persons by sea; illegal, unreported and unregulated fishing; and intentional and unlawful damage to the marine environment. The discussion then turns to the measures coastal States can take to protect their maritime security interests in the EEZ in the context of the longstanding doctrine of exclusive flag State jurisdiction. The concluding section examines emerging international efforts to combat threats to maritime security on a regional basis and discusses a potential solution to treat maritime security in the EEZ as collective security interests to meet the jurisdictional gap.