This book provides an accessible introduction to the American legal system and is a vital resource to anyone interested in understanding how this social system works. Its focus is on law in practice, the role of the law in American society, and how the social context affects the living law of the United States. It covers the institutions of law creation and application, law in American government, American legal culture and the legal profession, American criminal and civil justice, and civil rights. Now in its fourth edition, the book has been widely used in both undergraduate and graduate courses as an introduction to the legal system. This new edition follows the same structure as the previous editions while providing a thorough updating and reworking of the text. This edition reflects upon what has happened in the years since the third edition was published in 2017, the rise of social media, the strains of climate change, the globalization of risk, the pandemic, and the immigration crisis. The book addresses how these events and evolutions have shaped our fundamental comprehension of the workings of the American legal system today.