Security of supply refers to governmental policies that aim to secure the availability of critical products at all times. The COVID-19 pandemic brought to fore the importance of such policies, as suddenly there was an overwhelming need for critical medical supplies that the markets were not able to fulfil. Following the pandemic, the EU has started to construct its own security of supply policy, although lacking an explicit competence for it. This Article shows how competence on security of supply is actually split between the EU and the Member States, and highlights the consequences of this division.