Overview of the Standardising and Integrating Alien Species data (SInAS) workflow that can be used to merge alien species databases. The workflow consists of three consecutive steps: 1. preparation of databases, 2. standardisation, and 3. merging. The standardisation step is subdivided into the standardisation of: 2a. terminology, 2b. location names, 2c. taxon names, and 2d. event dates (i.e., first records). The user can modify the workflow by adjusting the reference tables under ‘user-defined input’. At each step of standardisation, changes and missing entries are exported as intermediate output that can be used to check the workflow, the reference tables, or the input data.