Thischapter defines the book’s object of study and explains its significance in linguistics and philosophy. It then discusses the book’s theoretical framework, its intended readership, and its topical emphasis, and it summarizes the book’s remaining chapters. In a nutshell, the book is about the semantics of propositional attitude reports: sentences centered around clause-embedding psychological verbs like Beatrix thinks it’s raining or Beatrix wants it to rain. Such sentences bear on foundational issues in the philosophy of language concerning the nature of sentence meaning and proper names. They also interact in intricate ways with many semantically relevant grammatical phenomena of interest to linguists specializing in semantics. This book surveys the key data, concepts, and theories concerning the compositional interpretation of attitude reports, assuming a model of grammar that includes a generative syntactic component that assembles structures and an interpretive semantic component that assigns truth conditions to those structures. The book is meant for students and researchers of linguistics who have had at least one or two graduate-level courses in formal semantics.