We sought to develop a quality standard for the delivery of psychotherapy for posttraumatic stress disorder (PTSD) that is both consistent with the underlying evidence supporting psychotherapy as a treatment for PTSD and associated with the best levels of symptom improvement. We quantified psychotherapy receipt during the initial year of PTSD treatment in a 10-year national cohort of Department of Veterans Affairs (VA) users who completed patient-reported outcome measurement as part of routine practice. We added progressively stringent measurement requirements. The most stringent requirement was associated with superior outcomes. Quality of psychotherapy for PTSD in the VA improved over time.