Social phobia and avoidant personality disorder were new diagnoses in the third version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III) and were considerably changed in the revised third version (DSM-III-R). A high rate of comorbidity between these disorders was observed, which can be explained by the use of the same diagnostic criteria for both conditions. While there has been considerable research activity on social phobia, little has been done on avoidant personality disorder. The relationship between these disorders, therefore, cannot be clearly stated at the moment. All of the empirical evidence so far supports a spectrum concept of social phobia with avoidant personality disorder rather than seeing the latter as a valid mental disorder.