The purpose of this study was to evaluate a newly designed peer support training program for first responders titled Recognize, Evaluate, Advocate, Coordinate, and Track (REACT). REACT was developed in partnership with public safety agencies to address the need for promoting psychological health. This resulted in the development of a program that uses train-the-trainer methodology to address primary prevention of stress injuries. REACT was an all-day training that consisted of four modules, each featuring instruction and practice. Six public safety agencies totaling 30 individuals (76.9% from four fire departments, 23.1% from two emergency communication centers) participated in REACT. The primary outcomes were knowledge and training-related self-efficacy; secondary outcomes included general self-efficacy, resilience, and improved attitudes and expectations. A peer-support model, using a train-the-trainer methodology, is a promising approach for addressing the promotion of psychological health.