Since its inception in 1991, the International Committee on the Underwater Cultural Heritage has advocated for the better legal protection, preservation and professional standards relating to underwater cultural heritage. In Heritage Under Water at Risk: Threats, Challenges and Solutions, ICUCH’s second contribution to ICOMOS’ Heritage at Risk series, there are 30 articles representing 23 countries spanning Asia and the Pacific, Arab States, Europe and North America, and Latin America and the Caribbean. With such geographical diversity there is inevitably a wide range of themes and scope of underwater cultural heritage found in, rivers, lakes, cenotes, as well as coastal and offshore marine environments. The volume is divided into five sections: legal and policy frameworks; challenges and solutions; preservation in situ; public engagement, and capacity building, noting that some papers span more than one theme. The focus is aimed at presenting examples of where heritage is at risk, but where applicable, also presenting sustainable solutions. The diversity of themes represented in the book underlines ICUCH’s knowledge and experience which provides it with a strong platform to remain an important and influential force in all matters relating to cultural heritage located in inland waters, coastal and underwater environs. By so doing ICUCH will continue to demonstrate the importance and relevance of the ICOMOS Charter on the Protection and Management of Underwater Cultural Heritage (Sofia 1996) that underpins the fundamentals of the committee’s formation and purpose.