Katherine Levine Einstein, David M. Glick, and Maxwell Palmer, political scientists at Boston University, conducted the first comprehensive study of who participates in local land use meetings and what effects this participation has on housing development. Their research, drawing on original data from Massachusetts communities, reveals a stark pattern: those who show up to planning board and zoning meetings are older, whiter, longer-tenured residents who overwhelmingly oppose new housing construction. The authors term these participants 'neighborhood defenders' and demonstrate how their outsized voice in local politics systematically restricts housing supply. The book explains the mechanisms through which this participation bias operates: politicians respond to those who show up, and developers anticipate opposition by seeking fewer permits for smaller projects than demand would support. The consequences extend beyond housing to exacerbate economic inequality, racial segregation, and environmental problems as workers are pushed into longer commutes. Einstein, Glick, and Palmer compare different institutional arrangements, showing how some communities have created processes that amplify opposition while others have found ways to approve needed housing. The book offers concrete recommendations for reforming local land use decision-making to better reflect community-wide interests rather than the preferences of the most mobilized opponents. Essential reading for anyone concerned with housing affordability and the peculiar ways American local government operates.