The final section of the book covers an array of special topics likely to include something of interest to most readers, followed by a chapter of concluding remarks. The topics, all related to the anxiety disorders under discussion, range across subject areas as diverse as genetics, neuroimaging, cognition, neurochemical markers, psychosocial factors, and anxiety in ethnic minorities. The most integrative among these is chapter 12, on neuroimaging. The authors, who undertake a systematic discussion of the fear neurocircuitry and a disorder-specific review of imaging studies, integrate these for the reader, discussing commonalities and specificities across the disorders, as well as limitations in imaging studies so far completed, further mapping out an agenda for future research.