The quality of the depressive experience in borderline personality disorder has always been perceived to be different from the depression experienced in major depression (MDD). This paper reviews those observations and studies of the particular ways in which this borderline personality disorder (BPD) depression/dysphoria has been described in the literature and makes note of the fact the patients with BPD often score more highly on self-rated scales of depression than on corresponding observer-rated scales. Often patients with BPD without MDD score as highly on depression rating scales as BPD patients with MDD and as highly as patients with MDD without BPD. Clinician-rated scales and operationalized diagnostic interviews do not easily capture the distinction between the depression of BPD and the depression of MDD. A fuller appreciation of the BPD patient's object relations, i.e., the nature of the interpersonal relationships and the person's reactions and affects to and within those relationships holds the key to understanding the nature of the quality of the depression of BPD.