+ Biodiversity cannot flourish in fragmented habitats so green infrastructure must be interconnected. Nature and cities can live together successfully -- if we pursue a long-term vision that recognises and embraces the value of green infrastructure and biodiversity to society. In his post on cities under stress , Bruce Sterling encourages us to ask what we want from our cities. The answer, surely, must be ecologically rich urban environments. As Tom Armour noted, planting large species trees in urban environments brings a host of social, environmental and economic benefits. Who wouldn't want to share their city with plants that have been shown to improve physical and mental health, reduce hospital recovery times and increase workplace productivity? But despite studies on the benefits of fostering nature in cities, the value of green infrastructure is too often overlooked -- with engineering solutions preferred to environmental solutions. Considering the wider picture and taking broader benefits into account will lead to greener solutions that provide great economic and multifunctional benefits. I believe the knowledge and technology we need to create rich natural environments in cities already exists; the problem is applying it. And what's vital is that any action should be implemented in a coherent, coordinated way to realise long-term benefits. The whole is greater than the sum of its parts, and if smaller interventions are coordinated and based around an overarching vision, the return on capital investment would increase greatly. What's more, the investment needed to realise huge rewards is tiny when compared