Posttraumatic stress disorder (PTSD) may develop after exposure to an event in which death, severe physical harm, or violence occurred or was threatened. First responders, including police, fire rescue personnel, and emergency dispatchers, have been viewed as populations at high risk for developing PTSD symptoms. Indeed, over 80% of first responders report experiencing traumatic events on the job, and it is estimated that 10–15% have been diagnosed with PTSD. However, to date, limited research has reviewed the impact and services available following these traumatic events across first responders. This review examines research regarding PTSD in police officers, firefighters, and emergency dispatchers with particular attention to the prevalence, comorbid diagnoses, risk and protective factors, and resources available to each group. A discussion of limitations of the available research in this area, and suggestions for directions that future work might take, are offered.