This text book is about the economics of air navigation services. Itis intended to be mainly an aid for students of air transport at the Faculty of Operation and economics of Transport and Communications during their stidies at University of Žilina, however, a broader circle of readers /practinioners as well/ is not precluded. The book has written to reveal ˝economics in the sky! or ! economics of the sky˝ in such a way to cover crucial economic aspects of air navigation services - economic nature of the industry, ownership and governance models, specifics of air navigation services costs management, air navigation services funding and charges for air navigation services, acomomic benchmaring of air navigation services probiders and enomomic portion within pervormance management of air navigation services providers.