How can a community follow smart growth principles?

My wife is a city planner of the sort that the first
answer refers to.  According to her, smart growth, at least in the context of the US,
means building cities with higher population densities and less
"sprawl."

If cities do this, then people will be closer to
the places where they work, shop, play, etc.  This means you need to have businesses,
homes, parks, and industry all relatively close together.  This will allow for more
walking and biking instead of driving.  Higher densities will allow for more transit
because more people will live within walking distance of bus or rail lines.  All of this
will lead to a decreased dependence on fossil fuel.

So the
core idea of smart growth is to use fewer resources.  To do that, you need to keep
cities relatively compact so that less driving is required.  This means having
businesses and even industry closer to people's homes and it means having more apartment
buildings and fewer single family homes.  This is one reason why it is so hard to get
places to follow smart growth principles.

If you follow the
first link below, you can find the US EPA's 10 principles of smart
growth.