Prevalences of Diagnostic Interview Schedule/DSM-III psychiatric disorders for male veterans and nonveterans from four war eras were estimated using data from over 7500 male community respondents interviewed by the Epidemiologic Catchment Area program at five geographic areas across the country. Veterans serving after Vietnam (Post-Vietnam era) had greater lifetime and 6-month prevalences of psychiatric disorder than their nonveteran counterparts, whereas the reverse tended to be the case for the Vietnam, Korean, and World War II war eras. Comparisons across war eras revealed a trend for more psychiatric disorder, especially substance abuse, in younger veterans and nonveterans than in older respondents.