Despite the high prevalence (as many as one in four) and severe impairment often associated with anxiety disorders, people who suffer are often undiagnosed, and may fail to receive appropriate treatment. The purpose of this volume is to provide a single resource that contains information on almost all of the measures that have demonstrated usefulness in measuring the presence and severity of anxiety and related disorders. This remarkable compendium includes reviews of more than 200 instruments for measuring anxiety-related constructs in adults. These measures are summarized in `quick view grids’ which clinicians will find invaluable. Seventy-five of the most popular instruments are reprinted and a glossary of frequently used terms is provided. This and the companion volumes in the series are written for practitioners who wish to make their assessment practices more systematic, want to have assessment devices readily available, and want to expand their assessment practices with the most up-to-date approaches.