Karst landscapes and karst aquifers are composed of a variety of soluble rocks, such as salt, gypsum, anhydrite, limestone, dolomite and quartzite. They are fascinating areas of exploration, study and research. As karst rocks are abundant on the Earth’s surface, the fast evolution of karst landscapes and the rapid flow of water through karst aquifers present many challenges from a number of different perspectives. This collection of 25 papers deals with different aspects of these challenges, including karst geology, geomorphology and speleogenesis, karst hydrogeology, karst modelling, and karst hazards and management. Together these papers provide a state-of-the-art review of the current challenges and solutions we face in describing karst from a scientific perspective, while at the same time providing useful data and information for managing karst territories to land planners, developers, and managers of show caves, natural parks and reserves in karst terrains.