Culturally and linguistically diverse (CALD) populations often have high rates of addictive disorders, but lower rates of treatment seeking and completion than the mainstream population. A significant barrier to treatment is the lack of culturally relevant and appropriate treatment. A literature review was conducted to identify relevant literature related to cultural competence in mental health services delivery and specifically treatment for addictive disorders. Several theoretical models of cultural competence in therapy have been developed, but the lack of rigorous research limits the empirical evidence available. Research indicates that culturally competent treatment practices including providing therapy and materials in the client's language, knowledge, understanding and appreciation for cultural perspectives and nuances, involving the wider family and community and training therapists can enhance client engagement, retention and treatment outcomes for substance use and gambling. Further methodologically rigorous research is needed to isolate the impact of cultural competence for the treatment of addictions and guide research to determine treatment efficacy within specific CALD populations. Training therapists and recruiting therapists and researchers from CALD communities is important to ensure an ongoing focus and improved outcomes for CALD populations due to the importance of engaging these populations with addiction treatment. Copyright © 2016 John Wiley & Sons, Ltd. Key Practitioner Message: The treatment needs of culturally diverse individuals with addictions are often not met. Theoretical models can guide therapists in incorporating cultural competence. Culturally targeted treatments increase recruitment, retention and treatment outcomes. Cultural competence includes matching clinicians and clients on linguistic and cultural backgrounds as well as being mindful of the impact of culture on client's experience of addiction problems. Few methodologically rigorous trials have been conducted to guide treatment practices and research needs to be incorporated into existing culturally relevant treatment services.