This study was a pilot for a larger study to evaluate a time-limited outpatient programme for adolescent anorexia nervosa, to explore the ability of an assessment interview to change self-reported motivation and ascertain the extent to which this predicted engagement with treatment and early behavioural change. Fortytwo adolescents with anorexia nervosa rated their motivation for change before and after attending a new-style assessment interview. Initial (6 week) effectiveness of the programme was evaluated by measuring engagement with treatment, weight change, clinician (HoNOSCA) and self-rated (EDI, MFQ, HoNOSCA-SR) outcome measures, overall and in relation to motivational status. The assessment interview significantly improved motivation. Motivational category after interview was unrelated to physical status, cognition or general functioning but predicted engagement with treatment. Whilst for the whole sample, treatment produced physical, cognitive and general improvements at 6 weeks, motivational status was a powerful predictor of weight gain. A clientcentred assessment interview engaged 80% in an outpatient programme based on CBT. Motivational enhancement may improve engagement and specifically result in behavioural change and early weight gain.