"Local" comes down to a 30- to 50-kilometer radius around a regional center. It help maintain ecologically diverse farming systems, support local farmers and food processors and avoid the environmental costs associated with the long-distance transportation of food. Purchasing food that is produced in environmentally responsible ways and processed and transported efficiently can make more ecological sense than buying directly from less efficient neighbors. Medium-scale, regional processing is where the greatest efficiencies are to be achieved. Other values like a preference for local, fair trade or sustainable production methods can shape purchasing decisions.