The sample was selected from secondary schools in Brisbane, Australia. The students completed a questionnaire that measured the dependent variable of willingness to seek help for a mental illness and the independent variables of attitudes toward mental illness, knowledge of mental illness, psychological functioning, perceived barriers to help-seeking, social support, and prior history of help-seeking. Consistent with previous findings, nearly 10 percent of the adolescents reported experiencing a mental illness in the past 12 months; and the finding that just over 30 percent of the sample reported experiencing an emotional, personal, or behavioral problem in the preceding 12 months agreed with findings from other samples of Australian adolescents. The findings indicate that adolescents with greater adaptive functioning, fewer perceived barriers to help-seeking, and higher psychological distress were more willing to seek help from both formal and informal sources. Greater social support was also related to the willingness to seek help from informal sources. Although adolescents' attitudes toward mental illness did not influence their willingness to seek help, less stigmatizing attitudes were related to higher knowledge of mental illness, being female, and having higher levels of social support. The finding that the number of perceived barriers is related to willingness to seek help has direct implications for mental health services. Interventions should focus on reducing significant obstacles to help-seeking, such as increasing adolescents' knowledge of the availability, affordability, and usefulness of various sources of help. Adolescents might be less reluctant to seek help from school counselors if confidentiality is ensured. 1 table and 30 references