A Downtown Improvement Area (DIA) is a public/private sector partnership in which property and business owners of a defined area elect to make a collective contribution to the maintenance, beautification and promotion of their commercial district. It is, in some ways, similar to a residential community association, but an appropriate analogy would be that of a suburban shopping mall, from which the idea for DIAs is, itself, modeled. Malls are generally single properties managed by one entity that rents out retail spaces to various tenants. Tenants pay a common maintenance fee to pay for services that enhance the appearance of the mall’s common areas and provide cooperative services for the mall and its various stores. DIAs operate in much the same way.

DIAs are grassroots organizations, that are driven by community support and require legislative authorization by the municipality in which they reside, in order to be established.

DIAs typically provide services such as street and sidewalk maintenance, public safety, park and open space maintenance, flowers and other beautifiers, events, and general image promotion. DIAs sometimes also work with private and public sector partners to facilitate capital improvements to public spaces. DIAs do not maintain or promote private businesses or properties and do not advocate directly on behalf of individual members. Rather, DIAs act to represent the collective voice of their mandated business district.

The services provided by DIAs are a supplement to the services already provided by the municipality.

In some areas, a DIA is referred to as a business improvement area (BIA), a business revitalization zone (BRZ), Business Improvement District (BID), or a community improvement district (CID).