This places such companies squarely in the middle of debates over the future of global food production, including concerns over food security, optimal land use and what kind of production systems can best feed the world. Nonetheless, companies seem to agree that buying from small farms, whether it be onions in Azerbaijan, milk in Colombia or mangoes in Kenya, is a positive development.

How to right-size sustainability

While working with small suppliers may be preferred or even necessary, effectively engaging them in supply chain sustainability programs takes additional work. Most companies' systems were designed with a relatively sophisticated, large-scale supplier in mind.

For example, suppliers may be asked to go through a formal audit or evaluation process involving questions about systems and policies for managing risk, health and safety, or environmental impacts. Such surveys often require that the companies have familiarity and access to computers and the Internet, which might not be the case for a small company in the developing world. Moreover, the paperwork required by a buyer's procurement team can be overwhelming for small suppliers with limited resources and management systems.

Working with suppliers that have no formal management systems and limited computer skills requires buyers to make a choice: outsource or adapt. Outsourcing means hiring an intermediary to communicate, translate and monitor sustainability expectations and performance. This might be done via a farmer's cooperative or through an integrated service provider that manages production, sales and transport.

The other option is to adapt, which most companies will have to do to some degree. For example, sustainable agriculture standards written for large farms in the U.S. context must be reimagined for a small Indian cucumber farmer: What expectations are meaningful and realistic?

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