What type of development involves the redevelopment of under-developed parcels within an existing community?

Infill development is a vital concept within urban planning that focuses on the redevelopment of vacant or under-utilized lots within existing urban areas. It aims to make efficient use of land already served by basic infrastructure and community services, enhancing the overall density of neighborhoods without expanding the urban footprint. By focusing on these under-developed parcels, infill development helps to revitalize communities, reduce urban sprawl, and promote sustainable practices by enhancing walkability and accessibility.

In contrast, urban sprawl refers to the expansion of a city into surrounding rural areas, creating low-density developments that often rely heavily on automobiles. Suburban expansion similarly describes the growth of residential areas outside of urban centers, leading to a spread of development into previously undeveloped regions. Greenfield development, on the other hand, involves building on previously undeveloped land, typically in rural areas, which can contribute to the loss of open space.

Focusing on infill development addresses urban challenges by promoting density and revitalization within the community context, making it the most suitable choice for the question.