Attachment theory was explored as a means of understanding the origins of personality disorders. We investigated whether adult attachment styles and personality disorders share a common underlying structure, and how both kinds of variables relate to family background factors, including parental death, parental divorce, and current representations of childhood relationships with parents. A nonclinical group of 1407 individuals, mostly adolescents and young adults, were surveyed about their attachment styles, parental marital status, parental mortality status, perceptions of treatment by parents in childhood, and 13 personality disorders. Results indicated substantial overlap between attachment and personality-disorder measures. Two of the personality-disorder dimensions are related to the two dimensions of the attachment space; that is, there is a two-dimensional space in which both the attachment patterns and most of the personality disorders can be arrayed. The one personality-disorder factor that is unrelated to attachment appears akin to psychopathy. Both personality disorders and attachment styles were associated with family-of-origin variables. Results are discussed in terms of encouraging further research to test the idea that insecure attachment and most of the personality disorders share similar developmental antecedents.