There has been scant empirical study of the psychological consequences of contemporary peacekeeping missions. This study examined relationships among 4 variables characterizing this type of operation (traditional combat events, negative aspects of peacekeeping, pressure to uphold restraint, and positive aspects of peacekeeping) and symptoms of posttraumatic stress disorder (PTSD). Participants were 3,310 male and female soldiers who served in the 1992-1994 Somalia mission. Structural equation modeling procedures were applied to data from subsamples of non-African Americans and African Americans. For both groups, traditional combat and negative aspects of peacekeeping were associated with PTSD, frustration with restraint, and positive aspects of peacekeeping; however, restraint was not related to PTSD. Discrepancies between the groups involved relationships among the restraint, positive aspects, and PTSD variables. Recommendations are offered to foster inquiry into this new research.