Immigrants, particularly asylum seekers and refugees, constitute a considerable patient population across various psychiatric care settings due to high rates of experienced complex and cumulative trauma as well as related mental disorders. In this chapter, we outline key challenges of clinical diagnosis of traumatized immigrant patients and propose culturally sensitive diagnostic strategies to avoid cultural biases and misdiagnosis. We give a brief description of this patient population and highlight differences to the local reference population that need to be considered in the context of mental health care. Our analysis leads to the following recommendations: if possible, employ trained interpreters or cultural mediators to bridge linguistic and cultural gaps; conduct a thorough psychiatric anamnesis, life story, and diagnostic exploration, including cultural assessment with the Cultural Formulation Interview; additionally, assess the symptomatic burden with cross-culturally adapted and validated psychometric instruments, mitigate stereotype projection through ongoing intervision or supervision, and use non-verbal tools when language barriers persist. Such a culturally mindful framework for clinical practice can increase diagnostic accuracy, improve therapeutic relationships, and enhance treatment outcomes for immigrant patient populations.