Anxiety sensitivity (AS) is the fear of anxiety sensations which arises from beliefs that these sensations have harmful somatic, social, or psychological consequences. Over the past decade, AS has attracted a great deal of attention from researchers and clinicians with more than 100 peer-reviewed journal articles published. In addition, AS has been the subject of numerous symposia, papers, and posters at professional conventions. Why this growing interest? Theory and research suggest that AS plays an important role in the etiology and maintenance of many forms of psychopathology, including anxiety disorders, depression, chronic pain, and substance abuse. Bringing together experts from a variety of different areas, this volume offers the first comprehensive state-of-the-art review of AS—its conceptual foundations, assessment, causes, consequences, and treatment—and points new directions for future work. It will prove to be an invaluable resource for clinicians, researchers, students, and trainees in all mental health professions.