We explore the role of tax administrations in the fight against inequality through data analysis of a survey consisting of 71 questions that we have designed and sent to the tax administrations of all EU Member States. The survey focuses mainly on the capacity concerning the enforcement of tax policies aiming at combating fiscal fraud and tax avoidance and on specific institutional aspects that can potentially explain a lack of enforcement. The paper explores the data we received from seven respondent jurisdictions and combines it with additional data available through the International Survey on Revenue Administration (ISORA). Our analysis covers, among others, topics such as the protection of whistleblowers, performance and staffing of large taxpayer offices, prosecution activities and the “revolving door”-phenomenon. These topics were chosen based on data gaps we identified in existing datasets available on capacity of tax administrations. Building on (preliminary) analysis of this data, we indicate several issues which we consider as potentially the most critical with regards to countering inequality; we also generate several hypotheses likely to be used in future research.