The Montana Youth Risk Behavior Survey (YRBS) is administered by the Montana Office of Public Instruction every two years to students in grades 7 through 12. The purpose of the survey is to help monitor the prevalence of behaviors that not only influence youth health, but also put youth at risk for the most significant health and social problems that can occur during adolescence. While all schools in Montana can participate in the survey on a volunteer basis, approximately 50 high schools are randomly selected to be included to provide the Montana statewide data to be used in other national YRBS reports. Data used in this report from the 2019 YRBS are based on a random sample survey of Montana high school students. The weighted data results contained in this report can be used to make inferences about the priority health-risk behaviors of all Montana high school students in grades 9 through 12. However, users should be careful in using the data since respondents in self-reported surveys may have a tendency to underreport behaviors that are socially undesirable, unhealthy, or illegal (alcohol consumption, drug use, seat belt nonuse, etc.) and overreport behaviors that are socially desirable (amount of exercise, etc.). [This report was prepared by the Youth Risk Survey Program, Health Enhancement and Safety Division, Montana Office of Public Instruction.]