Investigator shave documented positive associations between treatment responses for psychotherapy and agreeableness, a trait that encompasses interpersonal orientation; specifically, “agreeable” patient characteristics (e.g., trust, friendliness, warmth) have been associated with good treatment outcome, where as disagreeable patient characteristics(e.g., distrust, manipulativeness, control-seeking) have been associated with poor treatment outcome. Results for pharmacotherapy have shown the opposite result, such that low variants of agreeableness (e.g., low trust and straightforwardness) were associated with lower post treatment depression severity. It has been theorized that agreeableness impacts treatment outcome through its influence on the therapeutic alliance. For example, support for the influence of personality traits on client- therapist alliance and treatment outcomes would underscore the value of conducting pre-treatment personality assessments, as this data would inform prognostic utility and treatment selection de- terminations. For example, personality assessments may help illuminate the optimal foci of therapeutic change efforts, supply patients with realistic expectations of therapeutic gains, match treatment selection to patient personality traits, and facilitate the development of self in therapy. Despite its potential implications for treatment, investigators have yet to test directly the influence of patient personality traits on treatment outcome via their impact on therapeutic alliance among patients with MDD.