Numerous guidelines exist to inform decision-making regarding psychological treatment of patients with posttraumatic stress disorder (PTSD). While strides have been made in the implementation of evidence-based psychotherapies (EBPs) for PTSD in the United States. Department of Veterans Affairs (VA), a large population of veterans does not receive such services. Research has been conducted on veterans’ decisions to enroll in EBPs; however, less is known about providers’ perspectives related to offering trauma-focused therapies to the military and veteran population, particularly outside the United States. This study utilizes baseline data from a larger investigation aimed to support the sustained implementation of cognitive processing therapy (CPT) in U.S. VA and Canadian Operational Stress Injury (OSI) and Department of Defense settings. Providers who trained in CPT (N = 55) participated in interviews regarding their opinions of CPT, preferred treatments for PTSD, and their process in assessing appropriate PTSD treatments for each patient. A directed content analysis approach was used to identify themes for providers’ decision-making to utilize CPT within the context of four Consolidated Framework for Implementation Research (CFIR) domains. In the outer setting domain, providers reported disconnect from policy and leadership as a barrier, and in the inner setting CFIR domain, providers reported multiple facilitators: available resources, leadership support, and compatibility with CPT. The CFIR domain for characteristics of the individuals aligned with a theme of theoretical orientation and training as a facilitator. The intervention characteristics domain aligned with facilitators and barriers; complexity of CPT was a barrier, but relative advantage and perceived strength of evidence were facilitators toward implementation. The systems surrounding and supporting EBP delivery within the U.S. VA, Canada OSI, and Canadian Forces clinics have more similarities than differences regarding barriers and facilitators to delivering CPT. Despite variability in funding and training, provider experiences across all three systems suggest similar themes. Further investigation is needed to determine whether these findings extend to community samples or sites not yet offering EBPs.