The Rules for Navigation were established originally by custom and prudence some 400 years ago, but they were not presented in a codified form until 1863. Since then they have been modified several times, with the most recent modification becoming effective in September 1965.

The Rules apply to all British ships, together with those belonging to signatory countries of the International Conference on Safety of Life at Sea, 1960. They apply also to all ships navigating within British territorial waters, but, in areas governed by local rules, they serve to supplement not to override those local rules.