The placement of personality disorders on a separate axis in DSM-III reflects increased interest in their diagnosis and treatment and encourages clinicians to consider the effects of personality style on axis I clinical syndromes. In this review of axis II personality disorders, the authors discuss methodological issues related to the diagnosis of all personality disorders, review the use of various treatment modalities, and present current issues and controversies related to specific personality disorders. They urge that any revision of DSM-III incorporate more reliable and clinically meaningful criteria, perhaps substituting a multidimensional classification system for the current categorical model.