Brownfields: Abandoned or under-used industrial or commercial sites where redevelopment is complicated by real or perceived contamination.

Density: 1) The number of residences per acre; 2) population by the acre or square mile. Also referred to as gross density (the density of all land areas with a site or municipality, including nonresidential land) or net density (the density of residential land only). Density can be carefully designed to be extremely livable. Well-designed density is a critical component of successful infill.

Density bonus: A reward to a developer who provides a community benefit such as affordable housing or open space. The bonus is permission to build additional square footage or more units than zoning would otherwise allow.

Excellent design: Not merely the design of a building; but the design of all elements vital to the creation of healthy communities, from the shop sign to the regional transit system.

Exclusionary zoning: Zoning that restricts lot sizes uniformly, usually to one or two acre parcels per single-family house. Exclusionary zoning allows only one type of housing to be built. It encourages the development of large land parcels, often consisting of high-priced homes, usually at densities too low to support transit or neighborhood retail.

Greenfields: Natural or agricultural lands often threatened by conventional development.

Inclusionary zoning: Zoning that allows for varied density within a development site. Inclusionary zoning can result in a broad mix of housing, from rental apartments to owner-occupied homes.

New Urbanism: New Urbanism is a national movement that views disinvestment in central cities, the spread of placeless sprawl, increasing separation by race and income, environmental deterioration, loss of agricultural lands and wilderness, and the erosion of society’s built heritage as one interrelated challenge.  New Urbanism stands for the restoration of existing urban centers and towns within coherent metropolitan regions, the reconfiguration of sprawling suburbs into communities of real neighborhoods and diverse districts, the conservation of natural environments, and the preservation of our built legacy.

Mixed-use development: In the best sense, mixed-use development combines housing, shopping, workplaces, civic functions, and open space in one walkable neighborhood; preferably connected to an existing urban area and served by transit.

REIT: Real-Estate Investment Trust.

Smart Growth: A blanket term for the congruent movements to channel new growth into existing communities and build new subdivisions as compact neighborhoods as a means of curtailing sprawl and its effects.

Sprawl: A term that describes the low-density, isolated, automobile-dependent development patterns common in suburban communities.

Successful infill development: Successful infill development makes cities and towns more livable while conserving natural resources at the periphery of the metropolis. It replaces the need for sprawl by drawing development away from natural areas and farmland and concentrating economic growth in existing urban areas.

TND: Traditional Neighborhood Development (TND): A newly built neighborhood that is designed to include many of the necessities of life within a five-minute walk. To make the neighborhood affordable to a wide range of incomes, a variety of housing types are included, from single-family homes to accessory apartments, live-work, and apartments above storefronts. TNDs have a fine-grained street network to minimize walking distances, plentiful civic space, and housing that faces the street. Many TNDs use back alleys for garage and utility access.

Transit-Oriented Development (TOD): A mixed-use community within an average 2,000-foot walking distance to a transit stop and core commercial area. TODs mix residential, retail, office, open space, and public uses in a walkable environment, making it convenient for residents and employees to travel by transit, bicycle, foot, or car.

Unsuccessful infill development: Single-use projects with negative effects that far outweigh their economic or social benefits. Unsuccessful infill disrupts neighborhoods, historic districts, or natural environments; creates traffic congestion and air pollution while failing to provide alternatives to driving; contributes less than its share to the local economy; or otherwise detracts from the vitality of an existing community. Examples can include poorly designed or located residential subdivisions, big-box stores, sports stadiums, or office parks.