The world is urbanizing at an unprecedented pace—more than half of humanity already lives in cities, and by 2050 this will rise to nearly 70% (UN, 2022). While this rapid growth fuels economic progress, it also triggers mounting problems: choking traffic, polluted air and water, overflowing waste, degraded land, and rising climate risks. To keep our cities livable, we must embrace sustainable environmental management that balances growth with ecological limits and social fairness. A powerful pathway is the green economy, driving renewable energy, circular practices, smarter waste management, and green jobs—transforming cities into healthier, more resilient places for generations to come.