In this new era of global environmental concerns and economic competition between the world's metropolitan areas, basic questions about the sustainability of the greater Chicago region must be considered. Foremost among these concerns are the increasing pressures on the supplies of two of our most vital and interrelated resources -- land and water. Factors like the amount of open space, density of new development and intensity of farming practices greatly affect the quantity and quality of the region's water resources. Conversely, the quality and quantity of the region's lakes, streams and underground aquifers have a major influence on local land use decisions. Sustainable land use practices are essential to meet increasing demands for clean water. Although the quality of surface water in northeastern Illinois has improved in the past three decades, the supply remains limited by pollution from stormwater runoff, U.S. Supreme Court decisions capping the amount that can be drawn from Lake Michigan, steadily increasing urbanization of the region, inefficient water supply systems and unregulated groundwater withdrawals. To determine how to address these problems across a 12-county region in northeastern Illinois, the Joyce Foundation provided support to the Metropolitan Planning Council and Openlands, in partnership with the Campaign for Sensible Growth, to undertake a study to examine the relationship between development practices, land use, and water quality and quantity. This study addresses five areas: the state of the region's water resources; the state and federal policies that impact water; regional watershed planning efforts; local development practices and model ordinances; and techniques for reducing the impacts of urbanization on regional water resources.