The Science Needs Document is a comprehensive summary of the science support needed to meet the management goals of the Long Island Sound Study (LISS). It has been developed based on the input from a diverse array of LISS partners. It is structured around the Themes and Ecosystem Targets of the 2015 Comprehensive Conservation and Management Plan (CCMP). This is a broad reference document that is meant to highlight needs but not to specify the top priorities and is subject to continuous revision to incorporate new information.