Permaculture is a branch of ecological design, ecological engineering, and environmental design which develops sustainable architecture and self-maintained horticultural systems modeled from natural ecosystems.[1][2]

The core tenets of permaculture are:[3][4]

Take care of the earth: Provision for all life systems to continue and multiply. This is the first principle, because without a healthy earth, humans cannot flourish.

Take care of the people: Provision for people to access those resources necessary for their existence.

Share the surplus: Healthy natural systems use outputs from each element to nourish others. We humans can do the same. By governing our own needs, we can set resources aside to further the above principles.

Permaculture design emphasizes patterns of landscape, function, and species assemblies. It asks the question, "Where does this element go? How can it be placed for the maximum benefit of the system?" To answer this question, the central concept of permaculture is maximizing useful connections between components and synergy of the final design. The focus of permaculture, therefore, is not on each separate element, but rather on the relationships created among elements by the way they are placed together; the whole becoming greater than the sum of its parts. Permaculture design therefore seeks to minimize waste, human labor, and energy input by building systems with maximal benefits between design elements to achieve a high level of synergy. Permaculture designs evolve over time by taking into account these relationships and elements and can become extremely complex systems that produce a high density of food and materials with minimal input. (http://en.wikipedia.org/wiki/Permaculture, Accessed on 19 February 2013)