Post-traumatic stress disorder (PTSD) is a leading cause of impairment in quality of life and functioning among Veterans. Service dogs have been promoted as a potential intervention for Veterans with PTSD, however research supporting their effectiveness is limited. In order to evaluate the potential benefits of either service dogs or emotional support dogs, the Department of Veterans Affairs designed a randomized multi-site clinical trial in which Veterans were randomly assigned to receive either a service dog or an emotional support dog. This National Academies’ Committee is tasked with reviewing the monograph that reports on the therapeutic outcomes of this trial.