Exclusionary zoning limits residential development over large areas, and even entire cities or towns, to single-family housing on large lots. Exclusionary zoning is unfair to people and families of modest means (many of whom are members of racial or ethnic minorities) because it sharply limits where they can live and thus their access to jobs, education, and a good quality of life. For these reasons, exclusionary zoning was found to violate the New Jersey Constitution in the Mount Laurel case. But exclusionary zoning is also an environmental problem because it is a primary ingredient of the accelerating pace of urban and suburban sprawl. As a consequence, it is a major contributor to increased air and water pollution and habitat fragmentation. The Oregon planning program demonstrates how the abolition of exclusionary zoning promotes a more equitable range of housing choice in suburbs and simultaneously reduces environmental degradation associated with low-density urbanization.