Abstract: Military personnel are at increased risk of PTSD and gambling disorder (GD), and the two disorders are frequently comorbid. It is likely that gambling may provide an escape- and avoidance-based means of coping with traumatic experiences and associated reminders. Despite the heightened risk, little is known about comorbid PTSD and GD in veterans or the responsiveness of this population to new or existing treatment approaches. Third wave behavioral therapies such as Acceptance and Commitment Therapy (ACT) target a transdiagnostic process - experiential avoidance - believed to be at the root of human suffering. While it is known that ACT shows considerable promise and may improve both PTSD and GD outcomes, research into the potential effectiveness of ACT among veterans is scarce. Here, we systematically review the evidence relating to the use of ACT for military populations with PTSD and/or GD. Next, we outline several areas that warrant further research and clinical treatment development. Finally, we evaluate the potential of ACT-informed treatment of avoidant-based coping in veterans experiencing problems related to PTSD and GD.