In this book, Robert Ellickson asserts that local zoning policies are the most consequential regulatory program in the United States. Many localities have created barriers to the development of less costly forms of housing. Numerous economists have found that current zoning practices inflict major damage on the national economy. Using Silicon Valley, the Greater New Haven area, and the northwestern portion of Greater Austin as case studies, Ellickson shows in unprecedented detail how the zoning system works and recommends steps for its reform. Zoning regulations, Ellickson demonstrates, are hard to dislodge once localities have enacted them. He develops metrics to measure the existence and costs of exclusionary zoning, and suggests reforms that states and the federal government could undertake to counter the detrimental effects of local policies. These include the cartelization of housing markets and the aggravation of racial and class segregation.