What does the UK's exit from the EU mean for health and the NHS? This book explains the legal and practical implications of Brexit on the NHS: its staffing; especially on the island of Ireland; medicines, medical devices and equipment; and biomedical research. It considers the UK's post-Brexit trade agreements and what they mean for health, and discusses the effects of the COVID-19 pandemic on post-Brexit health law. To put the legal analysis in context, the book draws on over 400 conversations the authors had with people in the north of England and Northern Ireland, interviews with over 40 health policy stakeholders, details of a film about their research made with ShoutOut UK, the authors' work with Parliaments and governments across the UK, and their collaborations with key actors like the NHS Confederation, the British Medical Association, and Cancer Research UK. The book shows that the language people use to talk about hoped-for legitimate post-Brexit health governance suggests a great deal of faith in law and legal process among 'ordinary people', but the opposite from 'insider elites'. Not What The Bus Promised puts the authors' knowledge and experiences centre frame, rather than claiming to express 'objective reality'. It will be of interest to any reader who cares about the NHS and wants to understand its present and future.