Over the past two decades, the organization and provision of air traffic control (ATC) services has been dramatically transformed. Privatization and commercialization of air navigation has become commonplace. Far-reaching reforms, under a variety of organizational structures and aviation settings, have occurred across the world, most notably in Canada, Britain, Australia, New Zealand, and South Africa. In contrast, innovations have lagged behind in other countries - including the United States. In addition, much recent attention has been given to aviation infrastructure and safety in Africa,...