A review of the literature provides support for values as an important factor which impacts clients' psychotherapy outcome in several ways. Perceived initial values similarity between client and therapist was found to be significantly related to more favorable evaluations of the therapist and of therapy. Initial similarity on broader philosophical values and dissimilarity on values related to clients' problem areas both appear to be significantly correlated with improved client outcome. Finally, clients' values do appear to converge with those of their therapists over the course of successful psychotherapy. The most consistent finding in a review of the research was that clients come to adopt the values of their therapists and that this convergence is significantly related to their improved psychotherapy outcome. Length of treatment was shown to be a significant factor for the occurrence of convergence. These findings place an ethical responsibility on therapists to acknowledge and evaluate the values they hold since these values will impact their clients. Since the current limited number of studies has used a wide range of values and outcome measures, comparison among studies are difficult. Future research which more systematically evaluates the relationships between client and therapist values will help to clarify which specific values and sets of values are significant for clients' improvement in psychotherapy. Seven pages of references complete the document. (NB)