Changing Archaic Zoning Laws
"The zoning problem afflicts both cities and suburbs and manifests itself in countless ways... What urban planners disagree about is whether the current system can be salvaged, or whether it should be scrapped altogether. Most cities are not ready to take the ultimate step. Chicago isn't going that far. Neither did Boston, Milwaukee, San Diego and San Jose. All of themretained the basic zoning conventions, even as they slogged through the process of streamlining the codes and rewriting them for the 21st century."
Thanks to The Practice of New Urbanism