Comprehensive overviews of or compilations on state-of-the-art meander-type fish passes and their scientific evaluation (functionality) are either lacking or only available in fragmentary form, whether in Germany or elsewhere. As this is a young technology, the experiences and knowledge of meander-type fish passes listed in national or international literature, directives and leaflets are relatively limited. The main initial goal of the described project was to collect data on facilities in order to describe the current state of the technology and to perform first 3d-hydronumerical simulations. Typical representatives of meander-type fish passes (C-, J-, H-type and some special versions) were extensively analysed. One reference facility (H-type) was selected and studied in greater detail. The characteristic values of the analysed facility proved to be within acceptable tolerances. The 3d-hydronumerical simulations also confirmed that the flow velocity in the slots does not exceed an average value of v = 1.5 m/s. Functionality was also confirmed in a study from 2004.