With the rapid advancement of Artificial Intelligence across all sectors, each day we are faced with urgent questions around how this technology can be used safely and effectively-and nowhere are these questions more complex than in the defence sector. Mariarosaria Taddeo provides a conceptual yet applicable and systematic analysis of the issues that arise with the use of AI in defence, broadening the conversation in an underdiscussed area and offering practical recommendations for policy-makers and practitioners. The book provides a comprehensive view of the ethical challenges around AI and explores real-world examples of how AI can be employed, including intelligence analysis, cyber warfare, and autonomous weapon systems. Centering her argument around the autonomy and learning capabilities of AI technologies, Taddeo creates a coherent ethical framework based in AI ethics and Just War theory to answer the question how can AI in defence be used for good and support policy-makers and practitioners to make informed choices when developing an ethical governance of AI in defence.