We determined the prevalence and correlates of depression, alcohol abuse and suicidal ideation among medical and business students in Trinity College, Dublin and University College, Dublin. We rated depression and suicidal ideation in the past month with the Beck Depression Inventory (BDI) and alcohol abuse with the CAGE. Of 539 students registered, 338 (62.7%) responded. 47 (13.9%) students were depressed, scoring > or = 10 on the BDI. 83 (24.6%) students had an alcohol use disorder (CAGE > or = 2). Alcohol abuse was more common among business students than medical students (AOR = 2.9; 95% C.I. = 1.7-5.1); there were no other inter-faculty differences. 20 (5.9%) students reported suicidal ideation in the last month. Suicidal ideation correlated positively with stressful life events (AOR = 1.4; 95% C.I.= 1.1-1.7), and negatively with social support (AOR = 0.6; 95/ C.I. =0.5-0.7). These findings suggest that students are a vulnerable group, and underscore the need for mental health education and psychosocial support services in universities.