Anxiety disorders are among the most prominent mental disorders of late life. The prevalence of anxiety disorders among younger adults was estimated at 7.3% of the population; a slightly lower rate of 5.5% was reported among older adults (Regier et al. 1988). Review of these reports, however, suggests that the rate of anxiety disorders in older adults may be underestimated because of older adults' reluctance to report symptoms, confusion of anxiety symptoms with symptoms of physical illness, and a lack of measurement instruments validated for geriatric populations. Across community surveys, prevalence rates for anxiety disorders in older adults ranged from 0.7% to 18.6% (Flint 1994; Klap et al. 2003). Another possible explanation for the range in reported prevalence rates is that the symptomatic makeup of anxiety disorders in older adults differs from that seen in younger adults. Older adults tend to report anxiety symptoms that do not necessarily fit a specific disorder. A naturalistic survey of primary care patients found that in older adults diagnosed with anxiety disorders, the most prevalent diagnosis was anxiety disorder not otherwise specified (Stanley et al. 2001). A portion of the empirical work on the psychotherapeutic treatment of anxiety in older adults focuses on symptoms rather than specific diagnostic categories.