The Decision supporting tool on interoperability (the Tool) is being developed as part of the Legal Interoperability ISA2 action, which aims to ensure that digital and interoperability aspects are considered in EU policies from their earliest stage. Upon the design of a new legislation that brings changes to existing digital environments, especially at a trans-European level, policymakers have to choose which would be the most effective and efficient approach for implementation. In this decision they may want to consider, among other aspects, the costs and benefits of including…