The project covers a demonstration of the Wavepiston wave energy concept. Numerical tools for estimation of structural design loads and absorbed power for the concept were developed, together with a tool to model the motion of the complete string structure. A 1:2 scale installation was designed, built and installed in the North Sea. With several iterations made on the detailed design during the tests conducted at sea, the reliability and power performance of the concept were improved considerably. The power output from the installation confirmed the predictions of the numerical tools. A business analysis was carried out using the numerical tools and wave data for reference sites selected according to the large attention from potential customers to the concept. The business analysis supports a viable market launch plan for Wavepiston.