Anxiety disorders are highly prevalent in adults and often coexist with depression. Patients with anxiety commonly present to their primary care doctors, or in other medical settings, reflecting a high utilization of medical services. Furthermore, some patients initially complain of only somatic symptoms before they are ultimately diagnosed with a primary anxiety disorder. Approaches to management include both nondrug and drug treatments, and pharmacotherapy has substantial evidence-based support for efficacy. Of the drugs available for use, an antidepressant, and in particular a selective serotonin reuptake inhibitor, is the preferred initial treatment for most patients. This choice is based on the drug's proven efficacy, favorable adverse event profile, relative safety in overdose, and better management of comorbid depression. The treatment of anxiety disorders has multiple potential benefits in systems of managed care. These include the ability to maintain remission or prevent relapse, a decrease in comorbid depression, promotion of adherence with improvement in quality of life, and reduction in claims for medical care. This overview of the anxiety disorders sets the stage for subsequent discussions of managed care datasets highlighting the opportunities for making informed decisions about access to care and treatment that can lead to economic benefits, especially in light of the Medicare Modernization Act.