Scientific environmentThis dissertation is the result of a collaboration between Institutt for Psykologisk rådgivning AS, the Department of Clinical Psychology, University of Bergen, and Arbeids-og velferdsetaten.Institutt for Psykologisk rådgivning and the Research Council of Norway each provided fifty percent of the project's funding. One such intervention, derived from Emotion-focused Therapy (EFT), is referred to as a two-chair dialogue. This intervention aims to enhance the emotional processing of individuals with regard to destructive self-criticism. More specifically, the intervention is expected to effect the arousal of emotions and help clients attend to and appraise their emotional experiences. The purpose of this dissertation is to investigate and explore the impact of the two-chair dialogue intervention.Twenty-four clients presenting with destructive self-criticism were recruited from a Norwegian public mental health program, meant for people who are on sick leave due to depression and anxiety, which is the most common mental health difficulties. In this study a multiple baseline design was used. Each client was assigned to a baseline phase comprising either 5, 7, or 9 sessions. For the baseline phase, the therapists were asked to focus on the relationship aspect of EFT, that is, they were required to empathically attune to the clients' emotional experience, provide validation and reassurance for the clients' emotional experience, while complying with the basic Rogerian conditions of empathy, genuineness, and unconditional positive regard. In the second phase, we added a two-chair dialogue intervention for five consecutive sessions.This dissertation comprises three papers. For paper 1, all clients' sessions were recorded on video and analyzed with the Client Emotional Arousal Scale III and Experiencing Scale. Subsequently, it was investigated whether the phase which included the two-chair dialogue intervention was associated with a higher level of emotional processing in comparison to the baseline phase. Results suggest that the phase containing the two-chair dialogue intervention is associated with significantly more high-arousal episodes than the baseline phase. Experiencing increases 7 throughout the entire treatment, but not significantly more in the phase including the two-chair dialogue, suggesting that both phases are associated with enhanced emotional processing.In paper 2, we investigated whether the phase which included the two-chair dialogue intervention was marked by a significantly greater decrease in symptoms compared to the baseline phase. Here, results suggest that adding the two-chair dialogue intervention is associated with a more substantial decrease in depression-and anxiety-related symptoms, in comparison to the baseline phase. A closer analysis of the symptoms of depression indicates that the majority of reduction effected in depressive symptoms is related to the somatic-affective and not the cognitive components of depression. Destructive self-criticism exhibited reduction thro...