A cross-sectional survey of 1,431 homeless adults was conducted during the winter of 1989-90 at three shelters in Santa Clara County, CA, with a 98 percent response rate. Of the 1,008 U.S.-born men, 423, or 42 percent, were veterans, including 173 combat-exposed veterans and 250 noncombat-exposed veterans. There were 585 nonveterans. Both combat and noncombat-exposed veterans were significantly more likely to report excessive alcohol consumption before their initial loss of shelter than were nonveterans. Combat-exposed veterans had the highest prevalences of psychiatric hospitalizations and physical injuries before homelessness, 1.5 to 2 times higher than nonveterans and noncombat-exposed veterans. The length of time between military discharge and initial loss of shelter was longer than a decade for 76 percent of combat-exposed veterans and 50 percent of noncombat-exposed veterans. The extended time from discharge to homelessness suggests that higher prevalences of alcohol consumption, psychiatric hospitalization, and physical injury among veterans, especially those exposed to combat, may not have arisen from military service. It is possible, however, that such disorders may be considerably delayed before becoming serious enough to impact one's family, work, and the availability of shelter.