Active_comparator: Treatment as usual (TAU)

Participants randomized to TAU will continue to receive standard buprenorphine or methadone maintenance treatment from their current treatment provider and complete follow-up assessments as described above. However, they will not receive posttraumatic stress disorder treatment. Staff will mail participants an emergency naloxone kit containing two naloxone doses with simple instructions, a list of resources and contact information for mental health providers and other relevant resources in their community and assistance contacting any resources of interest.

Experimental: Prolonged exposure therapy (PE)

In addition to receiving standard buprenorphine- or methadone-maintenance treatment from their current provider and completing scheduled assessments as described above, PE participants will also receive 12 individual sessions of prolonged exposure therapy scheduled weekly over the 12-week treatment period and delivered via a secure and university-supported telemedicine platform. Beginning in study week 1, PE participants will complete weekly 60-minute telemedicine-delivered prolonged exposure therapy sessions provided by doctoral or master's level therapists trained in prolonged exposure therapy.

Experimental: Prolonged exposure therapy + attendance contingent financial incentives (PE+)

Participants assigned to the PE+ condition will receive the procedures noted above for the PE group plus financial incentives delivered contingent upon completion of PE sessions.