In 1978, Australian ecologists David Holmgren and Bill Mollison coined for the first time the concept of permaculture as a systematic method. For Mollison, “permaculture is the philosophy of working with and not against nature, after a long and thoughtful observation.”  Meanwhile, Holmgren defines the term as “those consciously designed landscapes which simulate or mimic the patterns and relationships observed in natural ecosystems.” 
In 2002, Holmgren published the book Permaculture: Principles and Pathways Beyond Sustainability, defining 12 design principles that can be used as a guide when generating sustainable systems. These principles can be applied to all daily processes in order to humanize those processes, increase efficiency, and in the long term ensure the survival of mankind.
How to Integrate the 12 Principles of Permaculture to Design a Truly Sustainable Project