There are several urban areas close to the sea and other water bodies that may be adversely affected by erosion and flooding. Global climate change, including sea-level rise and more intense and damaging storms, will increase the threats of natural hazards in several areas. Mitigating and adapting to these risks in urban areas are huge challenges for society. There is a need for a proper decision basis to build a society that is economically, socially, and environmentally sustainable. By incorporating coastal hazard and risk mapping into spatial planning, new developments can be diverted away from threatened areas. Further, by taking adaptation measures, risks in existing urban areas can be reduced. A guideline has been developed as a tool for the integration of costs and benefits in decision-making on investments in coastal zones. The guideline gives an overview of why, when, and how impact assessments and project appraisals can be made using socio-economic valuations of coastal areas affected by erosion. The guideline can be used to prioritise areas that need attention due to threatened shorelines, and to decide which preventive measures are the most efficient from a socio-economic point of view. Two case studies have been performed to demonstrate the practical application of the guideline and economic analysis and valuation in coastal management. This paper presents the results of the two case studies and discusses the prerequisites for impact assessment and project appraisal and how this is used and accepted by the users and decision-makers.