The Scottish Adjacent Waters Boundaries Order 1999 is a statutory instrument of the United Kingdom, defining "the boundaries between waters which are to be treated as internal waters or territorial sea of the United Kingdom adjacent to Scotland and those which are not". It was introduced in accordance with the Scotland Act 1998, which established the devolved Scottish Parliament.
The territorial waters thus defined as Scottish waters come under the jurisdiction of Scots law, and are also used for defining the area of operation of the Marine Scotland, the Scottish Environment Protection Agency, and other Scottish Government agencies and public bodies. This is, for example, of importance to the Scottish fishing industry, the North Sea oil industry, and in the competing claims for the resources of the Rockall Trough.
The territorial waters thus defined as not being Scottish waters come under the jurisdiction of either English law or Northern Ireland law. Therefore, because it defines the territorial limits of the three separate jurisdictions, it comprises a piece of constitutional law in the constitution of the United Kingdom.
