The fundamentals of attachment theory and family systems theory are outlined in this paper. Theoretical strengths and weaknesses of both approaches are discussed. First, the similarities of both approaches are analysed (focus on family relationships; focus on normal as well as disturbed development; status as metatheoretical perspectives). Then, the differences are outlined (empirical consolidation versus speculative theory development; integration versus abandonment of the concept of 'personality'; normativity versus non-normativity; deficit orientation versus resource orientation; dyadic versus triadic view; focus on past and present time versus focus on present and future).
PROBLEMAttachment theory and family systems theory both focus on interpersonal and, more specifically, on family relationships. Both are applicable to developmental as well as clinical psychology, and both were developed at about the same time.