The answer is nothing really unless you are looking to enrich incumbent property owners, institutionalize segregation and contribute to sprawl. That’s according to our guest, M. Nolan Gray, author of “Arbitray Lines”. He’s a professional city planner and an expert in land-use regulation. And while there are plenty of reasons to plan for diverse, inviting communities, the use of zoning is not a great tool in that effort. In the cities, it often limits the robust, multi-purpose neighborhoods of old that had a mix of housing types, small businesses and recreation areas to make life fulfilling without a car. And in the suburbs, while at times it may have some applicability to health and safety concerns with wells and septic systems, often zoning is used to excluded different types of people from finding their home in these communities. This could include limits on young people, the elderly and minority. Our guest explains why zoning is not to be equated with city planning and that it is not the only kind of land use regulation. In fact, he argues for its abolition.