The development of a hydropower facility has, in nearly all cases, some impact on natural river flows and the wider environment. This impact often includes the effect on fish, most notably curtailment of migration routes and changes to their natural habitat and ecosystem services fish is dependent on. The general relationship between fish and hydropower development and management has been the subject of extensive research for many years. However, most of the previous work has been based on a limited number of species, with the applicability of results on a global scale difficult to justify. With the further development of hydropower planned on a global scale, a program of international collaborative research is justified. This document identifies emerging best practices for managing hydropower and fish, by addressing relevant measures to mitigate changes in hydro-morphological conditions, water quality and quantity due to hydropower development. Where relevant, some of the most mature solutions are described as providing safe two-way connectivity for fish past barriers created by hydropower infrastructures. As such, it serves as a valuable resource for practitioners in the hydropower sector by providing a clear pathway toward viable solutions to the identified challenges for fish and hydropower.