"We can't solve these problems 50 acres at a time."

That was the message from Hal Hamilton and Susan Sweitzer, referring to the challenges facing the world concerning climate change, energy and water usage, soil quality, biodiversity and poverty. Hamilton and Sweitzer spoke as the 2009 W. Duvall Leaders in Residence during a recent visit to the University of Kentucky.

The couple founded the Sustainable Food Lab, a multi-continent project whose goal is to create mainstream, sustainable food systems. During their visit to the Lexington campus, they spoke to several groups focused on sustainability issues, including the UK Sustainability Advisory Committee; the College of Agriculture's Sustainable Agriculture and Food Systems working group; Annie's Project, a project designed to support and educate farm women; and a public forum that attracted community activists, representatives of big business and a local food cooperative.

After years as both community activists and farmers - they spent 15 years dairy farming in Henry County and now farm in conjunction with other families in an eco-village in Vermont -Hamilton and Sweitzer learned it was important to make the tight boundaries often found in the sustainable agriculture movement more inclusive, taking the movement beyond niche areas into the mainstream.

Lee Meyer, UK agricultural economist and chairman of the college's Sustainable Agriculture and Food Systems working group, agreed the sustainability movement must follow multiple paths if it's to be successful.

"We're really experimenting on how we're going to deal with some of the negative consequences of the production system that we have now," he said. "There are a lot of good things about it, but there's a list of tangible negative aspects too."

Meyer said it's possible to make great improvements in the economic, social and environmental pillars of sustainability within small segments of the food system. However, an alternative approach is to re-examine the larger arena of the conventional food system.

"If we can make small changes there, we can really have a large impact on the total system, maybe even greater than those really intense benefits from the niche areas," he said.

"Sometimes small steps by big players make a huge difference," Hamilton said during the public forum.

Consumers are part of the driving force motivating large companies to look for more sustainable methods of operating.

"As an economist, I think the biggest hurdle and the biggest opportunity is to get the consumers to look at the quality of their food and the way it's produced," Meyer said. "If they start making buying decisions that way, then that's going to start driving the whole system."

Hamilton said much of consumers' leverage stems from a company's desire for long-term profitability.

"The kind of drive to grow a successful business is a pretty powerful drive," he said. "If one can take advantage of that drive and hang on it goals for public good, then the possibility of achieving what we're all shooting for is so much better, so much more."

Through their Sustainable Food Lab, Hamilton and Sweitzer bring major food companies, such as Unilever, Kraft and General Mills, together with nongovernmental organizations including the World Wildlife Fund. It's not just about philanthropic donations to environmental causes. It's often about changing ways in which a company does business. According to Hamilton, World Wildlife Fund worked with Coca-Cola Bottling to improve the way they use water resources, and Unilever agreed to a moratorium on buying palm oil produced on deforested land.

Meyer said the food giants are looking around and realizing they might miss the boat unless they certify their products, whether that certification is based on environmental or humane standards. And from the UK College of Agriculture standpoint, Meyer said it's important to find ways to bring sustainable agriculture concepts to all Kentucky agriculture, whether small, organic farms, large-scale commodity operations, cow-calf producers or tobacco-growers.

Through his work with the Sustainable Food Lab, Hamilton has come to believe all strategies are "probably usable."

"The world of sustainability is pretty big," Hamilton said. "It's big enough for all of us."