Inclusion Criteria:  participants 18-years old or older fluent in English diagnosed with PTSD by a healthcare practitioner confirmed with the Clinician-Administered PTSD Scale for DSM-5 (CAPS-5 past month version) diagnosed with past-year substance use disorder other than tobacco or caffeine by a healthcare practitioner confirmed by Structured clinical interview for DSM-5 (SCID-5) agreed not to participate in other therapies during the program (mindfulness, yoga, biofeedback, self-hypnosis or tai chi) willing to commit to attend all sessions  Exclusion Criteria:  diagnosis of a severe or unstable medical illness that precludes safe participation in the study by a healthcare practitioner diagnosis of schizophrenia, schizoaffective disorder, or bipolar disorder; or current acute psychosis or mania by a healthcare practitioner participants with moderate or high risk of suicide upon screening by the Columbia Suicide Severity Rating Scale (C-SSRS) have an inability to communicate in English fluently enough to complete the questionnaire.