Treating patients with two or more personality disorders: an introduction

A high percentage of patients diagnosed with one personality disorder (PD) have, at the same time, at least one other PD. However, psychotherapists lack clinical guidance and research evidence on treating such complex patients. This issue of the Journal of Clinical Psychology: In Session attempts to bridge the gap. In this Introduction, the editors outline the subsequent articles in this issue and address the terminology, prevalence, and possible causes of Axis II comorbidity. They argue that comorbidity is, in part, ascribable to problems in classification systems and can be reduced by defining PDs in a more multifaceted manner. They provide several clinical vignettes to portray frequent difficulties encountered by psychotherapists in treating these complex, co-occurrent cases.