The goal of the current work is to provide a comprehensive review and interpretation of the literature on the human and economic burden of generalized anxiety disorder (GAD) and how it compares with that of other mental disorders. The term “human burden” is used to describe quantified impairments in role functioning and quality of life (QOL). “Economic burden” describes costs related to health care resource utilization and lost work. A review of 34 studies reporting original quantitative data on associations between GAD and role functioning, QOL, and/or economic costs was undertaken. GAD was defined by DMS-III-R, DSM-IV, or ICD-10 DCR. Persons with GAD (both with and without a comorbid mental disorder) described significant impairments due to both physical and emotional problems. Studies typically showed that role and QOL impairments of GAD were at least comparable in magnitude to those of other anxiety disorders, somatoform disorders, and physical conditions, and greater than those of substance use disorders. Large representative studies showed that role impairments of pure GAD were similar in magnitude to those of pure MDD. Studies of DSM-IV disorders showed that QOL impairments of GAD were at least comparable in magnitude to those of MDD; studies of DSM-III-R disorders showed the opposite pattern. GAD was associated with considerable economic costs owing to lost work productivity and high medical resource use. Quality of care initiatives that have been implemented to increase recognition and improve treatment outcomes for persons with MDD should be extended to the effective management of GAD. Depression Anxiety 0:1–19, 2006. © 2006 Wiley-Liss, Inc.