Food is the fundamental element for sustaining everyone everyday life. And Food system is the whole process that ensure crops be produced, livestock be raised, food be processed and then be distributed and sale, and for people to eat. With global economic development, things tend to be associated in global vision, and not except for the food system.
However, many problems, that now become huge obstacles, have been rooted in the global food systems when it began to develop. To conclude what is mentioned by Hough, farming, which is one of the most important processes of food system, is much too considered as business. He called it “agribusiness”.  In this sense, the relationship between human and agriculture has never been considered in harmony and coexistence, but utilization. As a result, few activities and few people are involved in the whole food system. Industrial food and global transporting for food are the main support to our diet. Most people only in the process of consuming. Under this misunderstanding of the relationship between agriculture and human, many environmental and social problems are caused by food systems. Hesterman said, for instance, environment issues: soil erosion and salinization, water pollution; land loss of farmland; climate change; diet and health issues: starving, hygiene problem of food, antibiotic overuse; and social inequality issues. 
In such a severe condition, the question is aroused, how could we overcome the issues? I think we are in need of a “retroactive design ” for the whole food system from the beginning. We need to think about how to treat farmland and agriculture. It should not be only for “recreation” and only for to fulfill “needs”. Economic factor of agriculture is important, but it does not definitely conflict with recreation, education, entertainment and etc. Farmland can be education center and recreation spot as the Culpepper Community Garden , and maybe exhibition and transaction center of newly-cultivated agriculture as well. Also, waste that are left in the producing process can be reused– hot water provides heat energy, residue becomes nutrient. The main point of the “retroactive design”, in my opinion, is trying to involve everyone in every process of the whole food systems. Then more people are not only consumers, but also participants that will spare no effort to contribute to a healthy food system.
When I went to Taiwan, the farm in National Taiwan University impressed me a lot. They raise livestock and produce dairy products to sell for the public, establish a museum to exhibit how rice develops in Taiwan and cultivate agriculture not only for sale but also research. Fortunately, the new type of park or green space—city farm is on the track. Various efforts are put into forming a healthier and more eco-friendly global food system. What is more, the ownership structure of farmland is needed to pay much attention, which is essential to every farm and industry.
- Hough, Michael. Cities and Natural Process: A Basis for Sustainability. London: Routledge. 2004.
- Hesterman, Oran. Fair Food: Growing a Healthy, Sustainable Food System for All. New York: Public Affairs. 2011.
- McDonough, William; Braungart, Michael. The Next Industrial Revolution. 1998.