Book excerpt: Adjudicative competence remains an important topic of research and practice in psychology and law. In the five sections of Adjudicative Competence: The MacArthur Studies, the authors present not only a summary of the research of the MacArthur studies on competence but also an examination of the underlying theoretical work of Professor Richard Bonnie. It is the first publication to encapsulate the scope and significance of both the studies themselves and Bonnie's contributions. There is no other source available that addresses this range of topics. Given its breadth and scope, this book will be a "must have" for forensic mental health professionals, an important volume for lawyers, and a vital academic reference work.