To study mobility behaviours and images of transport modes of teenagers in Europe, we organized a web-based survey in 2016. The population concerned is composed of teenagers (14-17 years old) living in five European countries (France, Germany, Great-Britain, Italy and Spain). Knowing the difficulty to reach teenagers through telephone and postal surveys, especially in five different countries, we decided to create a web-based survey. To recruit respondants, we paid for targeting advertising on Facebook, with a Facebook page for each country. To measure the impacts of advertising, we used several tools, from Facebook and from the survey platform. This poster aims at drawing lessons of this methodological experience and making some propositions for future surveys. Web