The purpose of this study was to determine the prevalence of inappropriate dietary behaviours, smoking and low levels of physical activity among high school students (n = 318) in Stratford, Ontario. Weight and height and 24 hour recalls were collected through individual interviews with 59 students. Over 1/3 (36.2%) of students were defined as current smokers; 42.8% reported eating breakfast on a daily basis; boys participated in physical activity more than girls (X2 = 4.79; p < .05). Mean intakes of energy, calcium, folate and zinc intakes were below recommended levels for both boys and girls. Findings indicate that these risk factors are prevalent among adolescents and that health behaviours cluster. These behaviours can increase the risk of chronic disease in adulthood. Strategies must be implemented to help adolescents develop lifelong healthy behaviours.