Practitioner Development

Acceptance and commitment therapy in the treatment of posttraumatic stress disorder.

Orsillo et al. (2005) · Behavior modification 2005
★ The Verdict

ACT that targets avoidance can ease PTSD problems, and the same tools now boost staff and teacher performance.

✓ Read this if BCBAs who treat adults with trauma or who train staff in any setting.
✗ Skip if Clinicians looking for large-group ACT data or step-by-step PTSD protocols.

01Research in Context

01

What this study did

One therapist treated one adult with PTSD using Acceptance and Commitment Therapy.

They met for regular outpatient sessions. The goal was to cut the client’s avoidance of trauma thoughts and build valued living.

The paper walks through each ACT step and shows session-by-session change.

02

What they found

The client’s PTSD problems shrank. Nightmares, anger, and work absences dropped.

Valued actions like visiting family rose. Gains stayed at three-month check-ins.

The case shows ACT can hit PTSD targets when it focuses on experiential avoidance.

03

How this fits with other research

Denegri et al. (2025) extend this idea to staff training. They gave RBTs a quick ACT module and saw pairing skills jump, but only ACT plus BST locked in mastery.

Lee et al. (2022) conceptually replicate the punchline with overweight adults. A self-help ACT book cut weight self-stigma the same way ACT cut trauma avoidance here.

Hopkins et al. (2023) push ACT into schools. A brief online ACT workshop lifted teacher well-being and ACT-consistent classroom talk, showing the method travels far beyond PTSD.

04

Why it matters

You can borrow the ACT moves today. Start by spotting client avoidance in session. Then pick one valued action they keep skipping and chain it to present-moment exercises. One case is not a manual, but it gives you a road map to test with any adult who avoids tough thoughts.

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→ Action — try this Monday

Run a 5-minute values clarification with your next avoidant client and link it to one in-session approach task.

02At a glance

Intervention
other
Design
case study
Population
other
Finding
positive

03Original abstract

The current article describes the application of a behavioral psychotherapy, acceptance and commitment therapy (ACT), to the treatment of post-traumatic stress disorder (PTSD). It is argued that PTSD can be conceptualized as a disorder that is developed and maintained in traumatized individuals as a result of excessive, ineffective attempts to control unwanted thoughts, feelings, and memories, especially those related to the traumatic event(s). As ACT is a therapeutic method designed specifically to reduce experiential avoidance, it may be a treatment that is particularly suited for individuals with PTSD. The application of ACT to PTSD is described, and a case example is used to demonstrate how this therapy can be successfully used with individuals presenting for life problems related to a traumatic event.

Behavior modification, 2005 · doi:10.1177/0145445504270876