Results from administering the Core Alcohol and Drug Survey on 61 US campuses during the 1994/95 academic year were analyzed to assess weapon carrying among college students. Seven percent of the 26,225 students (11.1% of the men and 4.3% of the women) responded that they had carried weapons (gun, knife, etc) during the last 30 days. A comparison with a matched sample of nonweapon carriers revealed that a greater percentage of the armed than the unarmed students had experienced harassment, violence, and threats of violence, and that they felt less safe on their campuses. The weapon-carrying men consumed significantly more alcohol than their unarmed counterparts, and a higher percentage reported binge drinking, use of other drugs, and adverse consequences from substance abuse. Differences between armed and unarmed female students were not as clearly consistent in terms of substance abuse and consequences.