This questionnaire was created for the project LIFE RIPARIAS , to assess the scope and accessibility of Belgian sources of invasive alien species data. It was sent to representatives of several Belgian data providers and discussed with them in online interviews. The results of the questionnaire serve as a business analysis for the software development in LIFE RIPARIAS preparatory action A1 . The document contains questions regarding: General information : contact details, general context Scope : questions related to the taxonomic, geographical and temporal scope of the data source Methodology : how were the data collected? Data : questions related to the (meta)data quantity and quality Sharing : questions related to the sharing conditions and publication frequency ; This work was funded under the European Commission LIFE programme (LIFE19 NAT/BE/000953).