The International Convention for the Safety of Life at Sea (SOLAS) is an international maritime treaty which sets minimum safety standards in the construction, equipment and operation of merchant ships. The convention requires signatory flag states to ensure that ships flagged by them comply with at least these standards. The current version of SOLAS is the 1974 version, known as SOLAS 1974, which came into force on 25 May 1980. As of March 2016, SOLAS 1974 had 162 contracting states, which flag about 99% of merchant ships around the world in terms of gross tonnage.
SOLAS in its successive forms is generally regarded as the most important of all international treaties concerning the safety of merchant ships.