BACKGROUND: Healthcare providers working in addiction facilities do not often implement integrated treatment of comorbid substance use disorder (SUD) and posttraumatic stress disorder (PTSD) while there is empirical evidence to do so. OBJECTIVE: This study aims to get insight into the views of clinicians with regard to the diagnosis and treatment of PTSD in SUD patients. METHOD: A qualitative research method was chosen. Fourteen treatment staff members of different wards of an addiction care facility were interviewed by an independent interviewer. RESULTS: Despite acknowledging adverse consequences of trauma exposure on SUD, severe underdiagnosis of PTSD was mentioned and treatment of PTSD during SUD treatment was not supported. Obstacles related to the underestimation of PTSD among SUD patients and to the perceptions of SUD clinicians concerning the treatment of comorbid SUD/PTSD were reported. CONCLUSIONS: It is concluded that SUD facilities should train their clinicians to enable them to provide for integrated treatment of SUD/PTSD.