Pharmacotherapy represents an important part of the care of patients suffering from PTSD and related problems and has been the focus of intense research efforts in recent years. As a clear reflection of progress in this regard, a large number of psychotropic agents have become available for the treatment of these conditions, and the majority of PTSD patients benefit from such interventions. These pharmacotherapeutic agents include tricyclic antidepressants, (TCAs), neuroleptics, benzodiazepines, and lithium (Smith, Cartaya, Mendoza, Lesser, & Lin, in press). Recent literature has clearly indicated that ethnicity and culture often exert important influences on the clinical effects of these potent therapeutic agents. These issues are highly relevant for the clinical care of PTSD patients with ethnic minority backgrounds.In this chapter, we first review the principles of how ethnicity may interact with drug metabolism and drug action. Next, the role that ethnicity plays in relation to the specific classes of medications that are commonly used to treat PTSD-antidepressants, neuroleptics, benzodiazepines, and lithium-is covered. Finally, we briefly discuss future research directions and the applicability of this research to clinical practice.