In contrast to the prognostic validity of the type-D personality, there is still little knowledge on the construct validity. In a sample of 102 healthy young adults the construct validity was analysed against the Big-Five dimensions, four of the 16 PF factors, and repressive emotion regulation. Social inhibition was associated with Apprehensiveness, and low scores in social competencies and self-deception. The three non-type-D clusters clearly differed; the restrained cluster emerged as opposite to the type-D cluster in nearly every personality dimension and type of emotion regulation. The article concludes that emotion regulation in socially inhibited persons deserves further investigation.