Book excerpt: For decades, nuclear deterrence has been at the heart of the transatlantic relationship between the United States and Europe. It underpins European security, and the North Atlantic Treaty Organization (NATO) continuously commits to remaining a nuclear alliance as long as nuclear weapons exist. And yet, with a few important exceptions, transatlantic dialogue on nuclear issues largely declined with the end of the Cold War, particularly among non-governmental experts--and has only started to be revived in recent years. Rebuilding deterrence dialogue in response to a shifting strategic landscape is an important step in strengthening not only the transatlantic partnership, but also European security. This paper collection explores the evolving deterrence dialogue in Europe and identifies ways to inject new momentum into that dialogue. Renewed attention on the issue is particularly timely as European actors confront an adventurist Russia, rising China, and new technologies that will impact nuclear deterrence, U.S.-Europe relations, and institutions such as the Nuclear Non-Proliferation Treaty.