This book aims to synthesize recent theoretical and experimental findings from psychology, neuroscience, epigenetics and genetics to understand anxiety disorders and their etiology and treatments. Each anxiety disorder is discussed from cognitive, behavioral and biological perspectives. The book evaluates talk therapies, mindfulness-based interventions, brain stimulation, biofeedback and neurofeedback treatments. Chapters consider a biologically-informed framework for the understanding of anxiety disorders. In line with current thinking, the book integrates many levels of information (from genomics and circuits to behavior and self-report) to understand normal and abnormal human behaviors. Synthesizing recent research on anxiety disorders according to their categorization in the DSM5, this book will bring psychology students, researchers, psychiatrists and psychologists up to date.