We examined the comorbidity of anxiety disorders and their clinical consequences in adolescents. The 1,035 adolescents, aged 12 to 17 years old, were randomly selected from 36 schools in the province of Bremen, Germany. Anxiety disorders and other psychiatric disorders were coded based on DSM-IV criteria using the computerized Munich version of the Composite International Diagnostic Interview. The comorbidity rate within the anxiety disorders was relatively low (14.1%). However, the comorbidity of anxiety disorders with other psychiatric disorders was high. Approximately half (51%) of the anxious adolescents had other psychiatric disorders. The most common comorbid pattern was that of anxiety and depressive disorders. Among those with both anxiety and depressive disorders, a majority of them (72%) had anxiety before that of depression. Anxious adolescents with comorbid disorders were significantly more psychologically distressed, as assessed using the SCL-90-R, and used more mental health services than adolescents with anxiety disorders only. The effect of comorbidity on mental health services utilization was stronger in males than females. The findings suggest the need to design intervention strategies to deal with cases with multiple disorders. Depression and Anxiety 18:1–6, 2003. © 2003 Wiley-Liss, Inc.