The present communication focuses on traffic environments and children. Many globalisation effect as regard to children's environment are due to global value granted to the speed in every city day-to-day life : communication speed, execution speed, moving speed... This strong value provides a whole dialectical in which children are very often trapped or prisoner and often on the same side: static vs dynamic; passant by vs drivers; reduced mobility vs hyper-mobile, attached to a territory vs decentrated.