The authors examined the proposal that personality disorder categories may denote particular detrimental combinations of personality dimensions. A multiround economic exchange game (ten round trust game), conducted with university students pre-selected on basis of their personalities (N = 164), provided a framework within which to investigate inability to repair ruptured cooperation. This behavior, thought to be characteristic of patients diagnosed with DSM-IV borderline personality disorder, was predicted only by the combination of high Neuroticism and low Agreeableness. Our results highlight an advantage of the categorical approach, category labels being a much more economic means of description than the delineation of interactions between dimensions.