Originally developed within psychoanalytic psychotherapy, the therapeutic alliance has emerged as a widely studied pantheoretical change variable. In fact, a Google Scholar search for “therapeutic alliance” and “outcome” returns roughly 135,000 hits. The vast majority of these studies have reported on the relationship between the alliance and psychotherapy outcome. However, a smaller but growing literature has also examined the relationship between the therapeutic alliance and pharmacotherapy adherence and outcome. The therapeutic or working alliance involves an ongoing collaboration between patient and provider encompassing both task- and affectively-oriented features of their relationship. Specifically, it is often defined as: a) the extent of patient-provider agreement on treatment goals; b) collaboration on treatment tasks necessary for goal attainment; and c) the affective bond (e.g., caring, liking, trust) between patient and provider (1). Patient and provider-rated, as well as observer-rated instruments are represented in the alliance-outcome literature.