Bair, the author, begins by saying (Page 3): "Any planner worth his salt in the years ahead is going to have to be aware that in large measure he won't know what he is planning for." Planning is future oriented decision making, and that always means that unknowns are involved. Who knows what might happen?
This is a useful volume on city planning, covering such topics as basic principles in urban planning, planning and the general welfare, planning techniques, land-use regulations, and zoning.
Pretty straightforward, and a nice overall analysis of urban/city planning.