INTRODUCTION: Drop-out from treatment is a serious problem in eating disorders which remains poorly understood. The present study investigated whether self-image and interpersonal theory could help to explain why eating disorder patients drop out of treatment. METHOD: Intake data on eating disorder patients who terminated treatment prematurely (N=54) were compared with patients who had completed treatment (N=54) and those who were still in treatment after 12 months (N=54). Self-image was assessed using the structural analysis of social behaviour (SASB), and comparisons were made on demographic and clinical variables. RESULTS: Patients who dropped out had initially presented with less negative self-image and fewer psychological problems compared with remainers. Low levels of SASB self-blame discriminated drop-outs from completers and remainers and significantly predicted treatment drop-out. DISCUSSION: Drop-out in eating disorders appears to be a complex phenomenon, not necessarily as pathological as often assumed. There may be important differences in the treatment goals of drop-outs and therapists; patients who drop out may be choosing to disengage at a time when symptom improvement creates space for closer examination of interpersonal issues.