The development of a Marine SAR Analysis and Interpretation System (MARSAIS) for application in the coastal zone is the objective of a current project, funded by the European Union. The system is aimed at the non-expert SAR user and integrates several state-of-the-art algorithms and multiple sensor synergy for quantitative interpretation of SAR data. In this work we focus on the part of the project that is concerned with the combined interpretation of SAR images and data from other sensors, and the ways in which this synergy improves our understanding of SAR monitoring of coastal processes.