The term "green infrastructure" is being applied at a wide range of landscape scales, from statewide conservation networks to streetside rain gardens. Fundamentally, green infrastructure is just a framework for recognizing the valuable services that nature provides for the human environment. At a bioregional scale, green infrastructure supports essential ecosystem functions. At a metropolitan scale, green infrastructure forms a tapestry of open space that serves and guides smarth growth. At a site scale, green infrastructure integrates functions and makes life-giving processes visible and meaningful. Large protected and connected natural habitats are the foundation for any regional green infrastructure network. Parks, trails, greenways, and other open spaces should link communities to each other and a regional landscape matrix. Holistically conceived, a green infrastructure network is also a regenerative solution to urban challenges associated with stormwater and waste management, mobility and public health, local food and energy security, and even protection from natural and man-made hazards.