H I Sutton writes extensively on maritime defense topics, particularly underwater warfare. For current events he uses OSINT (Open Source Intelligence) in addition to the usual tools and research. He writes for several publications and his own Covert Shores website (www.hisutton.com). He is the author of Narco Submarines, Covert Shores Recognition Guide which is the first book of its type. He has also published World Submarines, Covert Shores Recognition Guide and Covert Shores: The Story of Naval Special Forces Missions and Minisubs.