Social capital refers to acts of cooperation between two or more individuals or groups. While cultural capital is embodied in persons, social capital exists in relations among persons. The economic benefit of social capital is its ability to reduce transaction costs associated with formal coordination mechanisms such as contracts. This paper shows that communities in which people find it easier to co-operate will have higher levels of social capital than communities where collaboration is more difficult.Steps that counties can take to enhance social capital in their region are outlined, but policymakers should recognize that social capital is often a byproduct of religion and other factors that are beyond their control. A software is provided for sustainability researchers and practitioners to estimate community capital for each of the 102 Illinois counties.