The book (OUP, 2025) is the first systematic analysis of how the EU constitution has fared in wartime. It provides a comprehensive overview of the EU's response across a range of fields including common security and defense policy, economic policy, and energy policy. The book explores the long-term constitutional implications of the war for EU governance, and proposes legal reforms to address its shortcomings. It is a timely contribution on a topic of major social and political relevance - the war in Ukraine.