<P> Most of the urban poor in developing countries unable to find work, can spend their lives in insecure, poorly paid jobs . According to research by the Overseas Development Institute pro-poor urbanization will require labour - intensive growth, supported by labour protection, flexible land use regulation and investments in basic services .' </P> <P> Urbanization can be planned urbanization or organic . Planned urbanization, i.e.: planned community or the garden city movement, is based on an advance plan, which can be prepared for military, aesthetic, economic or urban design reasons . Examples can be seen in many ancient cities; although with exploration came the collision of nations, which meant that many invaded cities took on the desired planned characteristics of their occupiers . Many ancient organic cities experienced redevelopment for military and economic purposes, new roads carved through the cities, and new parcels of land were cordoned off serving various planned purposes giving cities distinctive geometric designs . UN agencies prefer to see urban infrastructure installed before urbanization occurs . Landscape planners are responsible for landscape infrastructure (public parks, sustainable urban drainage systems, greenways etc .) which can be planned before urbanization takes place, or afterward to revitalize an area and create greater livability within a region . Concepts of control of the urban expansion are considered in the American Institute of Planners . </P> <P> As population continues to grow and urbanize at unprecedented rates, new urbanism and smart growth techniques are implemented to create a transition into developing environmentally, economically, and socially sustainable cities . Smart Growth and New Urbanism's principles include walkability, mixed - use development, comfortable high - density design, land conservation, social equity, and economic diversity . Mixed - use communities work to fight gentrification with affordable housing to promote social equity, decrease automobile dependency to lower use of fossil fuels, and promote a localized economy . Walkable communities have a 38% higher average GDP per capita than less walkable urban metros (Leinberger, Lynch). By combining economic, environmental, and social sustainability, cities will become equitable, resilient, and more appealing than urban sprawl that overuses land, promotes automobile use, and segregates the population economically . </P>

When did the most rapid pace of urbanization occur
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