The paper is devoted to the issues of coastal protection using geosynthetic tubes filled with sand. It describes the technology of coastal improvement by SoilTain tube technology with a practical example of a dune protection on the beach in Rowy (Poland). The article presents assumptions taken in the design and the methodology of stability analysis. In addition it provides the results of measurements and verification of the design, details of the construction stages as well as the effect of a large storm three years after construction.