Generalized anxiety disorder (GAD) frequently occurs comorbidly with other conditions, including depression and somatic complaints. Comorbid GAD sufferers have increased psychologic and social impairment, request additional treatment, and have an extended course and poorer outcome than those with GAD alone; therapy should alleviate both the psychic and somatic symptoms of GAD without negatively affecting the comorbid condition. The ideal treatment would provide relief from both GAD and the comorbid condition, reducing the need for polypharmacy. Physicians need suitable tools to assist them in the detection and monitoring of GAD patients--the GADI, a new, self-rating scale, may meet this requirement. Clinical data have shown that various neurobiologic irregularities (e.g., in the GABA and serotonin systems) are associated with the development of anxiety. Prescribing physicians must take into account these abnormalities when choosing a drug. Effective diagnosis and treatment should improve patients' quality of life and their prognosis for recovery.