The present study aimed to elucidate dimensions of normal and abnormal personality underlying DSM-IV personality disorder (PD) symptoms in 168 adolescents referred to mental health services. Dimensions derived from the Big Five of normal personality and from Livesley's (2006) conceptualization of personality pathology were regressed on interview-based DSM-IV PD symptom counts. When examined independently, both models demonstrated significant levels of predictive power at the higher order level. However, when added to the higher order Big Five dimensions, Livesley's higher and lower order dimensions afforded a supplementary contribution to the understanding of dysfunctional characteristics of adolescent PDs. In addition, they contributed to a better differentiation between adolescent PDs. The present findings suggest that adolescent PDs are more than extreme, maladaptive variants of higher order normal personality traits. Adolescent PDs seem to encompass characteristics that may be more completely covered by dimensions of abnormal personality. Developmental issues and implications of the findings are discussed. © 2010, Copyright the Authors. Journal compilation © 2010, Wiley Periodicals, Inc.