Deep-water technology and commercial interests have put the protection of underwater cultural heritage under considerable pressure in recent decades. Yet the 2001 UNESCO Convention has the potential to fend off the threat—if fully implemented. This article sets out the legislative duties States Parties have under one of the Convention's core provisions: Article 16. It requires States Parties to take a triad of legislative measures: they must enact prohibitions, impose criminal sanctions and establish corresponding jurisdiction over their nationals and vessels. In addition, the comprehensive protection of underwater cultural heritage also necessitates measures covering acts of corporate treasure hunters, even though this is not required by the Convention itself.