This article provides a contemporary view of the psychodynamics of borderline personality disorder (BPD) from a developmental psychopathology perspective. We first briefly describe the evolution of the borderline construct in psychoanalysis and psychiatry. Then we provide clinically and empirically informed model of domains of personality function and dysfunction that provides a roadmap for thinking about personality pathology from a developmental psychopathology standpoint and examine the nature and phenomenology of BPD in terms of these domains of functioning. Next, we describe prominent dynamic theories of etiology of BPD and examine these in relation to the available research. Finally, we describe psychodynamic conceptions of treatment and the way BPD phenomena manifest in treatment, followed again by consideration of relevant research, particularly on transference-countertransference constellations empirically identified in the treatment of patients with BPD.