Neighborhood planning is a form of urban planning through which professional urban planners and communities seek to shape new and existing neighborhoods. It can denote the process of creating a physical neighborhood plan, for example via participatory planning, or an ongoing process through which neighborhood affairs are decided. The concept of the neighborhood as a spatial unit has a long and contested history. In 1915, Robert E. Park and E. W. Burgess introduced the idea of "neighborhood" as an ecological concept with urban planning implications. Since then, many concepts and ideas of a neighborhood have emerged, including the influential concept of the neighborhood unit. The history of neighborhood planning in the United States extends over a century. City planners have used this process to combat a range a social problems such as community disintegration, economic marginalization, and environmental degradation. The concept was partially employed during the development of new towns in the United Kingdom. The process has been revived as a form of community-led planning in England under the Localism Act 2011. Neighborhood planning process There is no set process for neighborhood planning. In some cases, such as statutory neighbourhood planning in England, regulations establish formal steps in the process such as being designated by the Local Planning Authority. The following six steps are typical of a general neighborhood planning process: Defining the neighborhood boundaries Public engagement and consultation Evidence collection Plan-writing Implementation Evaluation and monitoring The first step in planning for a neighborhood is to define the boundaries of the neighborhood. Neighborhoods can be difficult to define geographically, although neighborhood planning can work with all scales of area, from urban neighborhoods to rural areas. The process of defining boundaries can sometimes be problematic, for example if some areas do not want certain streets or houses to be included within a neighborhood boundary. More than one neighborhood district may attempt to claim a certain street or group of homes. Less problematic neighborhood boundary definitions are sometimes based on existing natural boundaries such as rivers, existing administrative boundaries, or based on census information. After the boundaries of the plan are established, those leading the plan should decide how to get the wider neighborhood involved with the planning process. To define the goals of the plan, public participation of local residents and stakeholders is often considered central. A city official may do all of the planning with minimal contact or input from