This section looks at the roots of green building, the various approaches to it, and from that creates a general overview of what it is.

Here we see that Green Building is in some way a fundamental departure from previous building techniques, but in others just an accumulation of additional concerns.  The idea that a building is an ecosystem that is situated in a larger ecosystem (its micro-climate) is so fundamental, that ignoring it can lead to bad results, no matter how many green checklist items a building might brag about.