The current paper is intended to provide an overview on the current state of the art for sandwich structures marine applications to support their wider application and identify the key issues to develop. A summary of current rules and standards on marine sandwich constructions is reported. The main critical points concerning design and qualifications are outlined, and some possible developments are suggested, with particular attention to critical loading conditions. An overview of innovative sandwich structures marine applications is included and some comparisons among different structures are provided. Some suggestions on future scenarios for sandwich structures marine applications are yielded.