Interventions Interpersonal Psychotherapy (IPT; Klerman et. al., 1984) is an evidence-based, time-limited treatment originally developed for treating Major Depressive Disorder, although it has been extended and developed for Bulimia Nervosa and recently also for Post-Traumatic Stress Disorder. The treatment is structured and focuses on relieving depressive symptoms by targeting interpersonal problems in the patients' current life situation. In the first four sessions an interpersonal problem area is identified that is asssumed to maintain the patient's depression and this problem is agreed upon as a therapy focus. Four types of focus areas are used in IPT: grief, role transitions, conflicts, and interpersonal deficits. In the middle phase of therapy the agreed upon focus area is worked with in a problem-solving fashion, and the patient is also encouraged to seek interpersonal support from his or her environment. IPT has been established as an evidence-based treatment for Major Depression (Roth \& Fonagy, 2005), and a recent meta-analysis concluded that it was slightly superior to other established treatments for MDD including Cognitive Behavior Therapy (Cuijpers, van Straaten, Andersson \& van Oppen, 2008).

Brief Relational Therapy (BRT; Safran \& Muran, 2000) is a relatively new version of Short-Term Psychodynamic Psychotherapy, based on relational psychoanalytic theory in combination with research on processes of rupture and repair of the therapeutic alliance. The therapeutic alliance, operationalized as the positive bond between patient and therapist in combination with agreement on tasks and goals of treatment, is the single most robust predictor of good outcome in psychotherapy research (Lambert \& Ogles, 2004). BRT was developed to help patients who had previously failed in psychotherapeutic treatment(s), presumably because of trouble in establishing a working therapeutic alliance with their therapist(s). Therapists are trained to be highly attentive to the therapeutic relationship and to signs of ruptures in the alliance, and to use self-disclosure and meta-communication about ruptures in order to repair the therapy alliance and at the same time help patients to develop a generalized capacity for observing self and others (mentalization). BRT has shown preliminary evidence for efficacy with patients who are at risk of negative outcome in psychotherapy (Safran, Muran, Samstag \& Winston, 2005) and with patients diagnosed with DSM-IV axis II personality disorders (Muran, Safran, Samstag \& Winston, 2005). A specific manual for BRT in Major Depressive Disorder is currently under development (Holmqvist, in preparation).

Both treatments consist of 16 therapy sessions which are all video-taped for adherence checks. The same therapists will provide both treatments, in randomized order.

Objectives The objectives of the study are to compare the new treatment BRT with the established treatment IPT in the alleviation of Major Depressive Disorder. The hypothesis of the trial is that BRT will be superior for patients who have more difficulty establishing a therapeutic alliance, while IPT will be superior for patients with less difficulty establishing a therapeutic alliance. Previous research indicates that baseline self-critical perfectionism negatively predicts outcome in IPT as well as several other brief psychotherapeutic treatments for depression, and that this is because self-critical perfectionism will cause problems in the therapeutic alliance (Luyten, Corveleyn \& Blatt, 2005). The primary hypothesis is thus that baseline self-cricial perfectionism moderates the relationship between treatment and outcome. Secondary exploratory objectives are to conduct in depth process research on the mechanisms of change in these treatments, as well as interaction effects between treatment modality and other patient characteristics.