Personality disorders have high prevalence rates of approx. 8% in the general population and up to 40% among psychiatric patients. The increasing amount of empirical and experimental research within the last ten years challenges our concept of personality disorders (PDs) with the following most prominent findings:

• • Longitudinal studies indicate much less stability than expected.

• • The DSM classification system hypothesis of a fundamental difference between axis I and axis II disorders has not been empirically affirmed.

• • Some of the current categories of disorders cover highly heterogeneous individuals and have low therapeutic implications.

• • The detection of neurobiological underpinnings of personality dysfunctioning points to a close interaction between nature and nurture in etiology.

• • Psychotherapeutic approaches developed for specific disorders have been proven to be efficacious; they rather favour a limited focus on maladaptive behaviors and attitudes instead of targeting a fundamental change of personality structure.

• • There is no empirical basis for polypharmacy; classes of psychotropic agents act on a rather broad spectrum of symptoms with no convincing database to suggest the combination of several drugs with respect to different targets.