The Global Maritime Distress and Safety System (GMDSS) is a set of protocols, equipment, and communications systems designed to ensure that if a ship is in distress, aid can be dispatched from anywhere in the world. Under the International Convention of the Safety of Life at Sea (SOLAS), all ships over 300 gross tonnage on international voyages must carry specified radiocommunications equipment, both satellite and terrestrial, for sending and receiving distress and safety communications.

Developed by the International Maritime Organization (IMO) in the 1970s in response to numerous maritime disasters (including the Titanic’s sinking years earlier), the full

implementation of the GMDSS took place in February 1999 and redefined how distress communications were sent. For the first time, ships far from land were able to send alerts directly to shore, rather than just to other ships, allowing shore-based facilities to take responsibility for coordinating necessary rescue efforts.

Today, the GMDSS is an integrated communications system that helps ensure that ships in distress do not disappear at sea, saving the lives of countless mariners. Under GMDSS requirements, all ships are required to be equipped with a variety of  communications instruments, including satellite terminals,

satellite emergency position-indicating radio beacons (EPIRBs), and NAVTEX receivers, to automatically receive shipping safety information.