Introduction to the special section on substance use disorder and posttraumatic stress disorder comorbidity

A body of 2 complementary, albeit independent, research literatures has eme rged that documents a strong relationship between substance use disorders ( SUDs) and posttraumatic stress disorder (PTSD) in both community and clinic al samples. Research on the concomitants and consequences of PTSD has found that substance abuse is a frequent comorbid problem among individuals diag nosed with PTSD. Researchers from the substance abuse field are now investi gating the interrelationship between PTSD and SUDs and finding that PTSD ha s a notable effect on SUD course and treatment response. Here, a brief summ ary of the prevalence of SUD-PTSD comorbidity is provided and the 5 article s of the special section are introduced.