Climate change, increasing natural disasters, food and energy crises, population growth, water scarcity and desertification, loss of biodiversity, degradation of ecosystems, migration, and growth of cities – the planet is currently facing a multitude of challenges. Mountain regions and their inhabitants are disproportionally affected, but also offer significant opportunities for solutions. By providing key environmental services such as freshwater, biodiversity conservation and hydropower to more than half of humanity, mountain ecosystems play a critical role in world development. Mountain systems are essential building blocks for long-term sustainable global development, poverty alleviation and the transition to a green economy. In a world heading towards water, food and energy crisis, sustainable mountain development is a global priority.