Where in the world can we find hope for a more sustainable future? Plenty of places, it turns out. In the Fall 2012 Momentum cover story, award-winning environmental journalist Hillary Rosner shines the spotlight on seven promising approaches to solving seven environmental grand challenges, from revitalizing ocean fisheries to shaping more sustainable cities. Also, explore new perspectives on hydropower, updates on an intriguing underground connection between Iceland and Kenya, a window on food waste, futurist Jamais Cascio’s take on jet packs and government, and more.