Objective: To evaluate childhood experiences (neglect and abuse), temperament and childhood and adolescent psychopathology as risk factors for avoidant and borderline personality disorders in depressed outpatients. Method: One hundred and eighty depressed outpatients were evaluated for personality disorders. Risk factors of childhood abuse, parental care, temperament, conduct disorder symptoms, childhood and adolescent anxiety disorders, depressive episodes, hypomania and alcohol and drug dependence were obtained by questionnaires and interviews. Results: Avoidant personality disorder can be conceptualized as arising from a combination of high harm avoidance (shy, anxious), childhood and adolescent anxiety disorders and parental neglect. Borderline personality disorder can be formulated as arising from a combination of childhood abuse and/or neglect, a borderline temperament (high novelty seeking and high harm avoidance), and childhood and adolescent depression, hypomania, conduct disorder and alcohol and drug dependence. Conclusions: Combinations of risk factors from the three domains of temperament, childhood experiences and childhood and adolescent psychopathology make major contributions to the development of avoidant and borderline personality disorders.