Tourism is a complex system within a dynamic framework that is exposed to rapid and challenging developments. The existing tourism research does not fully address the nature of the global, intertwined challenges that may affect and shape the worldwide tourism system in the future with respect to both the industry and society. This article contributes to eliminating this knowledge gap using an exploratory Delphi survey that seeks to identify the most prominent challenges to global tourism through 2020 and to understand their nature, drivers, and effects. The five proposed meta-challenges demonstrate the complexity of the interrelations and interdependencies affecting the future of the global tourism system. These meta-challenges may also be regarded as constituting a strategic road map for global tourism in a complex and dynamic world.