Acceptance and commitment therapy (ACT) for posttraumatic stress disorder (PTSD) is focused on reducing experiential avoidance and increasing psychological flexibility in the face of traumatic experiences. This approach involves using acceptance and mindfulness to help people who have experienced trauma to increase their commitment to values-based living. There is growing evidence for the potential efficacy of ACT for PTSD, with several pilot clinical trials showing reductions in PTSD symptoms and increases in quality of life, as well as improvements in ACT-associated processes. Future research should focus on larger clinical trials that evaluate the efficacy of ACT for people with PTSD.