VIS - Fish species introduction and recovery evaluation in streams and rivers in Flanders, Belgium is a sample based dataset published by the Research Institute for Nature and Forest (INBO). The dataset contains over 15,300 fish occurrences in over 400 samplingevents between 2007 and 2019 from 35 watercourses (strams and rivers) and enclosed waters. . The dataset includes more then 35 fish species and some crustacean bycatch. The data are collected to evaluate the success of the reintroduction of the fishes. Issues with the dataset can be reported at https://github.com/inbo/data-publication Length and weight measurement data of the individual fishes, absence information, occurrence data since 2013, as well as abiotic data of the sampling points (pH, temperature, etc.) are not included in the Darwin Core Archive and are available upon request. To allow anyone to use this dataset, we have released the data to the public domain under a Creative Commons Zero waiver (http://creativecommons.org/publicdomain/zero/1.0/). We would appreciate however, if you read and follow these norms for data use (http://www.inbo.be/en/norms-for-data-use) and provide a link to the original dataset (https://doi.org/10.15468/complete) whenever possible. If you use these data for a scientific paper, please cite the dataset following the applicable citation norms and/or consider us for co-authorship. We are always interested to know how you have used or visualized the data, or referenceto provide more information, so please contact us via the contact information provided in the metadata, oscibio@inbo.be or https://twitter.com/oscibio.