The Ecaap survey is a cross-sectional study targeting all adolescents enrolled in secondary school. It was conducted under the joint scientific supervision of INPES and the Polynesian Health Department, following authorization from the Minister of Education. In each randomly selected school, the survey was overseen by the principal. The survey questionnaire is based on a set of questions primarily concerning the use of psychoactive substances: tobacco, alcohol, tranquilizers and sleeping pills used off-label or without a prescription, pakalolo or paka (cannabis), and other illicit drugs (LSD, hallucinogenic mushrooms, ecstasy, cocaine, etc.). Other questions addressed perceptions of the risks associated with drug use, the availability of substances, problems encountered in connection with potential use, as well as leisure activities, family environment, pocket money, and feelings of unease... Since the questionnaire sometimes covers a recent period (the past thirty days), it was important not to choose a survey date immediately following school vacations (which often present specific opportunities for use). However, a trade-off had to be made between this concern and the need to survey students over a period relatively similar to that of the previous survey conducted in 1999 (January, February, March) in order to track changes in consumption over a given period, and to align with the European School Survey Project on Alcohol and other Drugs (ESPAD, March, April, May). The surveys were thus conducted from April to June 2009.[excerpt from chapter]