Eight-hundred and seventeen adolescent high school students in the Montreal region completed the DSM-IV-J gambling screen along with a questionnaire devised by the authors inquiring about their gambling behavior, including items assessing the types of activities in which they engage, frequency of involvement, reasons for gambling, and their cognitive perceptions of gambling activities. The results indicate that, in general, 80.2% of students reported having gambled during the previous year, with 35.1% gambling a minimum of once per week. Adolescents reported participating in gambling behavior more often than any other addictive behavior, including cigarette smoking, alcohol consumption, and illicit drug use. The mean age of onset of gambling behavior for the sample was 11.5 years. The rate of pathological gambling was 4.7% as measured by the DSM-IV-J. Pathological gamblers were more likely to have parents with gambling problems and to be engaging in illegal activities than non-pathological gamblers. Gender differences were evident, with males engaging in gambling activities more than females. Differences in game preferences were found, with males more attracted to sports lottery tickets and sports pool betting and females more attracted to lottery tickets and bingo. Gambling awareness and prevention issues are addressed.