1) The document discusses what is required for cities to be considered "smart cities" on a global scale. It examines trends in ecological footprints and biodiversity loss as well as the role of cities as centers of economic growth and urbanization. 2) Smart cities need to transition to low-carbon development through sustainable urban planning, renewable energy, green buildings, and engaging citizens to make sustainable lifestyle choices. The Earth Hour City Challenge recognizes cities that demonstrate global leadership in committing to and taking ambitious actions on climate change. 3) Cities require national and global support through knowledge sharing and financial innovation, as well as engaging citizens, to make progress toward becoming globally recognized smart cities that improve quality of life through sustainable urban solutions