Research in eating disorders is reviewed examining the (1) utility of the Transtheoretical Model in predicting outcome, and (2) efficacy of Motivational Interviewing (MI). There were promising results showing significant relationships between initial stage of change and treatment outcome related to eating pathology (not including purging), body mass index, and some aspects of psychopathology. Of those treatment studies utilising a control group, there was little indication that using MI conferred significant treatment benefit, with the exception of improving motivation and binge eating for people with binge eating disorder and bulimia nervosa. Overall the content of the studies varied greatly with relation to: stage of change and outcome measures, format of MI, diagnostic groupings, age of participants, utilisation of other adjunctive treatments, sample size, presence of follow-up assessments, and study design. Few of the 9 studies examining the efficacy of MI could be considered to have robust methodology. It is recommended that future research using the Transtheoretical Model to predict outcome adopt more uniform methodology so that we can more specifically determine its applicability, and that well-designed treatment studies in eating disorder populations be conducted so that we develop a stronger evidence base from which to decide whether MI confers benefit.