 Each of these large areas contains numerous neighborhoods, some of whose boundaries derive from the boroughs, townships, and other communities that constituted Philadelphia County before their inclusion within the city.The City Planning Commission, tasked with guiding growth and development of the city, has divided the city into 18 planning districts as part of the "Philadelphia2035" physical development plan.Much of the city's 1980 zoning code was overhauled from 2007 to 2012 as part of a joint effort between former mayors John F. Street and Michael Nutter.