The length of the growing season can limit sales of locally grown foods despite increasing demand. Season-extension technologies such as passive solar greenhouses ("hoop houses") have potential to address this constraint. This paper reports :findings from the first year of a project which measures the potential benefits of hoop houses to farm viabil­ ity and sustainability in three Michigan regions. We begin to determine the potential market for hoop-house-grown produce and whether consumers will patronize extended-season farmers. Using results from four methods (dot poster surveys, written surveys, focus groups, and experimental auctions) conducted at three Michigan farmers markets, we :find that consumers greatly value locally grown foods, are willing to patronize early- and late-season farmers markets, and report willingness to pay a premium for local produce. We explore the meaning and value of "local" from previ­ ous research and the contributions of hoop-house-grown produce at farmers markets to meeting demand for attributes associated with local produce. We conclude with observations on the role of season extension in the development of local sustainable food systems.