This longstanding casebook addresses the law governing the federal courts and their relationship to the state courts. In addition to reflecting substantial updates, the Tenth Edition has been reorganized to give instructors greater flexibility in choosing where to begin the course. There has also been some reordering of the chapters, but the book is not designed to compel that structure, and the chapters are self-contained. Some of the individual chapters have been modified as well to allow for greater choice in teaching. For example, the topic of justiciability is now covered in two chapters: one dealing with the basics and a second with a menu of additional issues that can be covered or omitted as desired. As has always been a feature of this casebook, careful attention has been paid to teachable units that permit reasonable class assignments.