This bestselling book provides an incomparable reference source for all vessels using maritime radio communication systems, which are now a legislative requirement. It includes exhaustive coverage of all UK and international regulations relating to modern maritime communications, such as the crucial GMDSS, all contained within one singular volume. This sixth edition has been fully updated to take into account major developments over the last five years, in particular the revised regulations introduced by the International Telecommunication Union in 2012. The authors deliver an authoritative guide to the complicated and changing world of radio communications, including: The very latest technological advances in terrestrial and satellite communications Changes to the international VHF channel allocation and channel spacing The major overhaul of the organisational structure of the UK Coastguard service Substantial enhancements to the eLoran services The changing complexities of voyage planning Large diagrams, an extensive index and fully-updated appendices This is a definitive guide for today’s maritime communications industry, including ship owners, ship managers, coast guards, seafarers, students of maritime communications, as well as the recreational sector.