The European Central Bank’s (ECB) role as a political actor during the euro crisis raised concerns about its independence and insufficient accountability. Against this backdrop, the article investigates how and why the ECB reacted to demands for more accountability during and following the crisis. To this end, we revisit the independence-accountability nexus, adding three qualifications to the conventional wisdom that independence and accountability do not go together. First, recurring to the governor’s dilemma, we argue that a delegation relationship characterized by a high level of independence favours competence over controllability. Second, we open the black box of accountability by investigating the extent to which the ECB made the strategic choice to improve selected accountability dimensions. Third, against the commonsensical view that ECB accountability mechanisms are underdeveloped, this piece shows that certain accountability dimensions have been continuously improved to defend independence. The findings contribute to the literature on accountability and the causes and consequences of delegating power to supranational institutions.