1. Military personnel exposed to war-zone trauma are at risk for developing PTSD. Those at greatest risk are those exposed to the highest levels of war-zone stress, those wounded in action, those incarcerated as prisoners of war, and those who manifest acute war-zone reactions, such as CSR. 2. In addition to problems directly attributable to PTSD symptoms per se, individuals with this disorder frequently suffer from other comorbid psychiatric disorders, such as depression, other anxiety disorders, and alcohol or substance abuse/dependence. The resulting constellation of psychiatric symptoms frequently impairs marital, vocational, and social function. 3. The likelihood of developing chronic PTSD depends on premilitary and postmilitary factors in addition to features of the trauma itself. Premilitary factors include negative environmental factors in childhood, economic deprivation, family psychiatric history, age of entry into the military, premilitary educational attainment, and personality characteristics. Postmilitary factors include social support and the veteran's coping skills. 4. Among American military personnel, there are three populations at risk for unique problems that may amplify the psychological impact of war-zone stress. They are women whose war-zone experiences may be complicated by sexual assault and harassment; nonwhite ethnic minority individuals whose premilitary, postmilitary, and military experience is affected by the many manifestations of racism; and those with war-related physical disabilities, whose PTSD and medical problems often exacerbate each other. 5. The longitudinal course of PTSD is quite variable. Some trauma survivors may achieve complete recovery, whereas others may develop a persistent mental disorder in which they are severely and chronically incapacitated. Other patterns include delayed, chronic, and intermittent PTSD. 6. Theoretically primary preventive measures might include prevention of war or screening out vulnerable military recruits. In practice, primary preventive measures have included psychoeducational and inoculation approaches. Secondary prevention has been attempted through critical incident stress debriefing administered according to the principles of proximity, immediacy, expectancy, and simplicity. Tertiary prevention has included psychotherapy, pharmacotherapy, dual diagnosis approaches, peer counseling, and inpatient treatment. Few treatments have been rigorously evaluated. 7. There are both theoretical reasons and empirical findings to suggest that military veterans with PTSD are at greater risk for more physical health problems, poorer health status, and more medical service usage. Much more research is needed on this matter. 8. Despite the potential adverse impact of war-zone exposure on mental and physical health, there is also evidence that trauma can sometimes have salutary effects on personality and overall function.