The compact city or city of short distances is an urban planning and urban design concept, which promotes relatively high residential density with mixed land uses. It is based on an efficient public transport system and has an urban layout which – according to its advocates – encourages walking and cycling, low energy consumption and reduced pollution. A large resident population provides opportunities for social interaction as well as a feeling of safety in numbers and "eyes on the street".<ref name = "jj">The Death and Life of Great American Cities (1961) New York: Random House. </ref> It is also arguably a more sustainable urban settlement type than urban sprawl because it is less dependent on the car, requiring less (and cheaper per capita) infrastructure provision (Williams 2000, cited in Dempsey 2010). Achieving a compact city does not just mean increasing urban density per se or across all parts of the city. It means good planning to achieve an overall more compact urban form: The compact city model, ideally, creates benefits that are attractive to modern urbanites. The desired benefits include shorter commute times, reduced environmental impact of the community, and reduced consumption of fossil fuels and energy. However, research on compact cities from around the globe suggests that these outcomes are not guaranteed. To make matters worse, the design of the cities is limiting residents’ access to green space and reasonable views. For the compact city model to gain in popularity, it is necessary to review both their pros and cons. Origins The term compact city was first coined in 1973 by George Dantzig and Thomas L. Saaty, two mathematicians whose utopian vision was largely driven by a desire to see more efficient use of resources. The concept, as it has influenced urban planning, is often attributed to Jane Jacobs and her book The Death and Life of Great American Cities (1961), a critique of modernist planning policies claimed by Jacobs to be destroying many existing inner-city communities. Among other criticisms of the conventional planning and transport planning of the time, Jacobs' work attacked the tendency, inherited from the garden city movement, towards reducing the density of dwellings in urban areas. Four conditions were necessary to enable the diversity essential for urban renewal: mixed uses, small walkable blocks, mingling of building ages and types, and "a sufficiently dense concentration of people". The 'sufficient' density would vary according to local circumstances