COLREGs
The international "rules of the road" governing how ships navigate to avoid collisions at sea.
COLREGs — the Convention on the International Regulations for Preventing Collisions at Sea — are the navigation rules every vessel must follow: who gives way, lights and shapes, sound signals, conduct in restricted visibility and in narrow channels and traffic separation schemes.
They are the maritime equivalent of road traffic law and are central to apportioning blame after a collision. Compliance is part of the safe navigation a flag and class regime is meant to ensure.
Also known as: COLREGs, collision regulations, rules of the road.
Related terms
International Maritime OrganizationIMO
The United Nations agency that sets global rules for ship safety, security and pollution prevention.
Classification Society
An organisation that sets technical standards for ship construction and surveys vessels against them throughout their life.
Automatic Identification SystemAIS
A VHF transponder system that broadcasts a ship’s identity, position, course and speed for collision avoidance and tracking.
Plain-English reference definition — our own explanation of a standard shipping concept, not a licensed source or legal advice. See the full glossary or the broader maritime dictionary.
Last reviewed: June 2026.