Abstract
Motives: Due to human activities, shoreline transformation processes are accelerating. The existing policy to protect them often results in costly and inefficient public investments that protect private investments. Such a policy is not only questionable in terms of the rationality of public spending but also fuels a vicious circle—further investments accelerate erosion.Aim: The objective of the study is to formulate guidelines for determining safe investment boundaries, grounded in the analysis of scientific research, legal frameworks, and case studies.Results: The study has made it possible to formulate criteria for defining the safe investment boundaries in coastal areas, develop a set of recommendations for effectively implementing this tool, and contribute to rationalising investment processes in coastal areas.