The idea of community looms large in the current environmental debate. It offers a locus of action that complements both the national and international protocols and the individual behavioral changes that have, until recently, dominated the environmental agenda.
The practice of designing and redesigning for sustainable community development, however, still lags far behind. We are just beginning to understand what makes some communities thrive while others struggle.
For a community to thrive in a complex environment, it must strike a delicate balance between planning proactively and remaining alert to emergent, unexpected changes. This dance of prediction and adaptation is a hallmark of the human response to the complex dynamic environments in which we live and work. The capacity of an individual or community to plan or initiate action is known as the exercise of agency.
Without agency, communities and indeed civilizations can be swept away by the challenge of change. As explored in the works of writers such as Joseph Tainter and Jared Diamond, societies who lose the ability to perceive emergent change and adapt are likely to fail.
Brian Walker describes resilience as the capacity of a system to undergo change and still retain its basic function and structure, an ability that is partly manifest through the proper functioning of agency. A lack of agency leads directly to a lack of resilience.
Agency through Food Choices
Food is the natural system that individuals and communities interact with most often and most viscerally. As such, agency over our food systems can be a powerful locus of community resilience.
Particularly in the industrialized world, food choices have largely passed out of individual or community control. One indicator of community agency is the presence of urban agriculture. At present, 15% of the world’s food needs are met through urban production, but for the most part, industrialized countries have been fully integrated into a global food system. 
Despite this fading of urban agriculture in developed nations, the potential is very large. For example, a pilot study in Vancouver, Canada estimated that 32% of the land area in a 3.4 acre residential city block was suitable for growing edible crops. 
The Cuban Experience
The experience of the city of Havana, Cuba demonstrates how effective urban agriculture can be at providing for local needs. The fall of the Soviet bloc was a massive emergent event that threatened the Cuban economy with ruin. Before the collapse of the Soviet block Cuba had regulations against many urban agricultural activities and there was a broad social taboo against growing one’s own food.
The fall of the Society Bloc led to a 75% decline in imports to Cuba, including a 50% drop in fertilizer imports. Fortunately, within the populace there was a remainder of knowledge on how to grow food locally; and in a surprising move the central government decided to give agency to the local populace to produce their own food for use and resale. Laws were relaxed and scientists helped develop intensive urban growing methods. The 5000 or so urban gardens of Havana now produce as much as 16kg of produce per square meter. 
The Cuban citizenry was successful at enacting agency over their food security in part because most of the urban dwellers retained knowledge of rural living, including knowledge of local crops. North Americans do not carry such knowledge to the same degree and face other barriers, including prohibitive bylaws; the difficulty of preparing the plot initially, animal and human predation; and difficult soil and microclimate conditions.
Urban Farming Entrepreneurship
The need to overcome these barriers has led to the rise of a new sort of entrepreneur; part landscaper, part farmer, part educator. Two such organizations are Your Backyard Farmer of Portland, Oregon in the U.S. and City Farm Boy of Vancouver, Canada. These small businesses provide the set-up and labour needed to create an urban garden plot, and then maintain the crop as it grows.