Objective: There is a critical need to better understand psychological treatments from a culturally sensitive lens. Using a process-oriented model, we examined treatment satisfaction among perinatal patients who received behavioral activation (BA) within a large psychotherapy trial for perinatal depression and anxiety, and explored how to optimize culturally sensitive delivery through a multistakeholder perspective. Method: In this mixed methods study, we estimated treatment satisfaction through mean client satisfaction scores (Client Satisfaction Questionnaire [CSQ]-8) among perinatal participants (N = 417) using one-way analysis of variance. We also conducted semistructured interviews with 20 ethnically diverse perinatal participants, 19 treatment providers, and five clinical leads. We employed content analysis to identify barriers, facilitators, and strategies for delivering culturally sensitive treatment. Results: CSQ-8 scores were similar across ethnic groups, F(7, 409) = 0.70, p = .67. Most participant interviewees reported that topics of race, ethnicity, and culture were raised during treatment sessions and that providers were able to address these topics in a culturally sensitive way. Despite this, almost all providers and clinical leads reported insufficient training to deliver culturally sensitive psychotherapy. The most-endorsed challenge for participants and providers was apprehension to bring up issues of race and ethnicity during treatment. Key facilitators included provider style, previous training, ongoing training resources, and supervision. Conclusion: BA offers one psychotherapeutic This document is copyrighted by the American Psychological Association or one of its allied publishers.This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.