Mental health treatments can be more effective when they align with the culture of the client and when therapists demonstrate multicultural competence. We summarize relevant research findings in two meta-analyses. In the meta‐analysis examining culturally adapted interventions, the average effect size across 99 studies was d = 0.50 (0.35 after accounting for publication bias). In the second meta‐analysis on 15 studies of therapist cultural competence, the results differed by rating source: Client‐rated measures of therapist cultural competence correlated strongly (r = 0.38) with treatment outcomes but therapists’ self‐rated competency did not (r = 0.06). We describe patient considerations and research limitations. We conclude with research supported therapeutic practices that help clients benefit from modifications to treatment related to culture.