The COVID-19 pandemic is a defining event of the 21st century. It has taken over eighteen million lives, closed national borders, put whole populations into quarantine and devastated economies. Yet while COVID-19 is catastrophic, it is not unique. Children who have been home-schooled during COVID-19 will almost certainly face another pandemic in their lifetime - one at least as bad-and potentially much worse-than this one. The WHO has referred to such a future (currently unknown) pathogen as "Disease X". The defining feature of a pandemic is its scale-the simultaneous threat to millions or even billions of lives. That scale leads to unavoidable ethical dilemmas since the lives and livelihood of all cannot be protected. But since one of the most powerful ways of arresting the spread of a pandemic is to reduce contact between people, pandemic ethics also challenges some of our most widely accepted ethical beliefs about individual liberty and autonomy. Finally, pandemic ethics brings vividly to the foreground debates about the structure of society, inequalities, disadvantage and our global responsibilities. In this timely and vital collection, Dominic Wilkinson and Julian Savulescu bring together a global team of leading philosophers, lawyers, economists, and bioethicists. The book reviews the COVID-19 pandemic to ask not only 'did our societies make the right ethical choices?', but also 'what lessons must we learn before Disease X arrives?'