Abstract: The presentation will give a view of the Swedish integrated work on finding the best available technique due to fish passages. This process includes a dialogue between managers, researchers and companies. The aim is to find the best techniques world wide and produce guidelines that can be used by companies, authorities and others in Sweden and maybe other countries (Norway is represented in the reference-group), working on developing the hydropower in an environmentally good manner. The presentation will give a wide brief of the difficulties and solutions due to legal requirements and implementations, targets on passage efficiency, prioritization etc.