This Special Issue "Advances in Sedimentology and Coastal and Marine Geology" brought together thirteen research articles and one review article, improving the state of the art of the corresponding sub-disciplines. Beach rocks, hybrid event beds, Quaternary marine sedimentation, and shallow gas represent important topics highlighted in this Special Issue. Different areas locations have been studied in the articles included, including both Mediterranean and extra-Mediterranean areas. In the Mediterranean areas, the Bay of Naples and the Cilento offshore (Southern Tyrrhenian Sea, Italy) have been studied, along with the Red Sea (Saudi Arabia). The content of this Special Issue significantly improves enhances previous knowledge of the marine geological and sedimentological processes of continental margins. The audience will include academics and researchers in the field of geology, geotechnical engineers, as well as geological scholars.