Understanding the dropout rates of efficacious forms of psychotherapy for patients with binge eating disorder (BED) is an unsolved problem within this increasing population. Up until now the role of psychotherapy process characteristics as predictors of premature termination has not been investigated in the BED literature. Within a randomized controlled trial (N = 78) we investigated the degree to which early psychological process characteristics, such as components of the therapeutic relationship and the experiences of mastery and motivational clarification, predicted premature termination of treatment. We statistically controlled for the influences of covariates such as rapid response of treatment, treatment group, body mass index, Axis II disorder, and patients' preexisting generalized self-efficacy at baseline. Patients' postsession reports from Sessions 1 to 5 indicated that low self-esteem in-session experiences was a stable predictor of premature termination. Its predictive value persisted after controlling for the above-mentioned covariates. Exploratory analyses further revealed low self-esteem experiences, low global alliance, and low mastery and clarification experiences as predictors in those patients who explicitly specified discontentment with therapy as reason for premature termination. These results indicate that patients' self-esteem experiences may not be an epiphenomenon of their specific psychopathology but may represent general mechanisms on which remaining or withdrawing from psychotherapeutic treatment depends. Early psychotherapy process characteristics should therefore be considered in training and evaluation of psychotherapists carrying through BED treatments. (Contains 5 tables.)