The reprint deals with different aspects related to sustainability and new technologies in coastal engineering, including innovation topics. Coastal engineering is a discipline in continuous evolution, where it is essential to seek a balance between the natural character of the coastal zone and the integration, to a greater or lesser extent, of human activities in that space. The present Special Issue had the objective of gathering scientific articles dealing with any aspect of coastal engineering related to sustainability or the use of new technologies. Manuscripts could have been focused on the past, the present, or what is expected in the future (short, medium, and long term). The manuscripts should have in some way shown concepts related to sustainability or the use of new technologies. Examples of topics that were welcomed in the Special Issue were environmental aspects related to maritime works (coastal, port, and offshore activities), coastal evolution, climate change, sea level rise and its influence in the design, construction, and/or maintenance of maritime infrastructures, sustainability aspects in the sea, marine renewable energies, including offshore wind, and novel aspects such as the use of new materials, the calculation of the carbon footprint, the use of neural networks, the use of BIM, etc.