Maritime Security Regimes are codes and conventions of behavior agreed upon by coastal states to provide a degree of security within territorial waters and on the high seas. Purpose One of the best known International Maritime Regimes is the United Nations Convention on the Law of the Sea, or UNCLOS. While UNCLOS is only one of many regimes, or sets of rules, laws, codes and conventions that have been created to regulate the activities of private, commercial and military users of our seas and oceans, it provides the legal framework for further maritime security cooperation. Most maritime regimes, including UNCLOS, have been created through the United Nations International Maritime Organization (IMO) in consultation with its member states, and refer to navigation, resource allocation and ownership, prevention of pollution and environmental protection. The United States has not yet ratified UNCLOS (see United States non-ratification of the UNCLOS) but it does adhere to its conventions, and has been the driving force behind other maritime security initiatives, including PSI, CSI, ISPS Code and counter-piracy agreements to address piracy against commercial shipping in the Gulf of Aden, Horn of Africa region. The United States has also led attempts to expand current bilateral maritime policing, counter narcotics trafficking agreements, whereby regional states in the Caribbean participate in a Caribbean Regional Maritime Agreement (CRA) - (long name: Agreement Concerning Co-operation in Suppressing Illicit Maritime and Air Trafficking in Narcotic Drugs and Psychotropic Substances in the Caribbean Area). Where maritime security regimes can differ from other maritime regimes, is that they are created to enable effective policing beyond the jurisdictional constraints of the territorial sea, which ranges from to from the high-water mark of a coastal state (see UNCLOS). Complications arise when a navy, coast guard, coastwatch, maritime police force, or other agency wishes to intercept (or 'interdict') vessels suspected of carrying out illegal activities, such as piracy against ships, smuggling or there is potential for an act of terrorism. If a suspect vessel is registered, or 'flagged', with a state other than the state of the pursuing authorities, then in most cases the pursuing authorities must gain the permission of the 'flag' state prior to boarding. If the suspect vessel crosses into the territorial waters of another state, possibly a third state, which is not the home state of the pursuing authorities, then permission must be sought from the territorial state prior to intercepting or boarding.