The paper shows that, contrary to expectations, the EU has in fact an extensive array of health crisis management capability for action at its disposal during pandemics. The paper points at an expanding institutional and formal role in public health for the EU, legitimized as responding to ‘health security’ demands and built up in the aftermath of major health threats, compositing around its limited legal competence in the field of public health. Health crises seem to serve as a ‘trigger’ to justify and legitimise an expansion the legal competence for the EU in the field of public health, with policy change in this sovereignty- charged area occurring in a ‘revolutionary’ rather than incremental fashion. The crisis mode seems to escalate the urgency of the problem-solving mode among the member states, leading to an expansion of EU’s role and of the legal and institutional framework for common action at the EU level, suspending traditional sovereignty objections to deeper integration.