Eating disorders (ED) and personality disorders (PD) co-occur together frequently, and the latter need to be considered by the treating clinicians as they can hinder treatment effectiveness or, if left unaddressed, can lead to relapse. These persons present with a combination of ED symptoms and behaviours, interpersonal problems and global suffering and often have difficulties forming and sustaining a therapeutic alliance. How can we address this condition so as to make ED treatment more effective? We describe the story of Silvia, a 34 years old woman with Binge Eating Disorder (BED) and PD treated with Metacognitive Interpersonal Therapy. She entered treatment with frequent binges and was seriously overweight (Body Mass Index= 36.7). She had difficulties describing her inner states and understanding why she binged, so she could not control them. During therapy, starting from the information coming from the food diary, she gradually becomes aware of how she processes underlying symptoms and interpersonal behaviour. The therapist used a combination of CBT techniques and experiential work, such as guided imagery, to foster change in both the ED and PD domains. By treatment termination, Sivia no longer suffered from either BED or PD and lost 10kg. This case is an example of how it is possible to combine aspects of treatment targeting ED with attention to PD features in an effective way. It also invites researchers to consider ED/PD comorbidity so as to reduce dropouts and increase treatment effectiveness