This book provides an introduction to contemporary constitutional law for intelligent readers who are not, or not yet, lawyers. It is a reasonably short book, which leaves out much detail. I have also done my best to write it in plain language – or at least to explain the jargon used by courts and lawyers before employing it myself. But the book does not talk down to the reader or omit central considerations. It aspires both to inform and to challenge nonlawyers who are interested in constitutional law, as well as law students seeking an introduction to the subject and lawyers who would like a refresher.

I still remember the intellectual thrill of my own first encounter with a book about constitutional law. It came in 1971, when I was a college undergraduate. The book was Robert McCloskey's The American Supreme Court, written in 1960. Over the years, when people have asked me to recommend a book introducing constitutional law to nonlawyers, I have usually named McCloskey's. Increasingly, however, I have done so hesitantly. The organization of McCloskey's book is mainly historical. It discusses successive eras in the history of the Supreme Court, often brilliantly, but without attempting to provide the clear portrait of contemporary constitutional law, and of the debates surrounding it, that some readers want. In addition, The American Supreme Court has inevitably grown dated with the passage of time, despite able efforts by one of McCloskey's former students to summarize recent developments in additional chapters. McCloskey's book naturally reflects the political and scholarly concerns of the period in which he wrote it, now more than four decades ago. It is time for a new introduction to American constitutional law, written in the twenty-first century for a contemporary audience.