Over the past two decades, the European Union (EU) has become a central actor in financial regulation and developed complex institutions to fulfill its roles. Pre-financial crisis scholarship has provided key insights into the functioning of this institutional cobweb and its evolution over time. However, the financial crisis has highlighted four facets of EU financial regulation (EUFR) that deserve more scholarly attention than they have received so far: (1) the permissive pre-crisis consensus on the merits of financial liberalization and integration, (2) the embeddedness of financial regulation in the political economy of EU integration at large, (3) preference formation of public and private stakeholders in EUFR, and (4) the global economic and regulatory context of EUFR. This paper presents the key scholarly challenges across these four areas. Addressing them promises not only academic insights but also promotes the relevance of EUFR research for real-world policy dilemmas.