The Green Infrastructure approach analyses the natural environment in a way that highlights its function and subsequently seeks to put in place, through regulatory or planning policy, mechanisms that safeguard critical natural areas. Where life support functions are found to be lacking, plans may propose how these can be put in place through landscaped and/or engineered improvements.
Within an urban context, this can be applied to re-introducing natural waterways and making a city self-sustaining particularly with regard to water, for example, to harvest water locally, recycle it, re-use it and integrate stormwater management into everyday infrastructure.
The multi-functionality of this approach is key to the efficient and sustainable use of land, especially in a compact and bustling country such as England where pressures on land are particularly acute.  An example might be an urban edge river floodplain which provides a repository for flood waters, acts as a nature reserve, provides a recreational green space and could also be productively farmed (probably through grazing). There is growing evidence that the natural environment also has a positive effect on human health.