The aims of this paper are to analyze differences in sociodemographic and clinical characteristics among the various anxiety disorders treated in a Psychology Clinic, and the results of treatment in each anxiety disorder. Data from 282 patients of University Psychology Clinic at the Complutense University of Madrid, who had at least one diagnosis of anxiety according to DMS-IV-TR criteria, were analyzed. The most frequent anxiety disorders were nonspecific anxiety disorder (19.1%) and social phobia (18.8%). Significant differences were observed according to sex (in all disorders, the percentage of women was significantly higher than that of men, except for obsessive-compulsive disorder). Unspecific anxiety disorder required a smaller number of assessment and treatment sessions, whereas obsessive-compulsive disorder required a greater number of sessions. There were no significant differences between the percentage of patients who completed treatment and dropout rates in specific phobia, general anxiety disorder and obsessive-compulsive disorder. Differences between epidemiological and clinical data are discussed.