Adaptive reuse is the process of adapting old structures for new purposes. When the original use of a structure changes or is no longer required, as with older buildings from the industrial revolution, architects have the opportunity to change the primary function of the structure, while often retaining some of the existing architectural details that make the building unique. In local communities, unused schools or Post Office buildings have been adapted for reuse as retail stores or offices.

Adaptive reuse, along with brownfield reclamation, is seen by many as a key factor in land conservation and reducing the amount of sprawl. For those who prescribe to the smart growth concept, it is more efficient and environmentally responsible to redevelop older buildings closer to urban cores than it is to build new construction on faraway greenfield sites.

In the United States, especially in the Northeast and Midwest, loft housing is one prominent result of adaptive reuse projects. The gentrification of formerly-industrial areas such as the Meatpacking District, Manhattan, New York and Callowhill, Philadelphia, Pennsylvania are being transformed into residential neighborhoods through this process. Waterfronts that once harnessed the current of rivers and lakes to speed production are now selling-points for home buyers and renters. Adaptive reuse can also take on less extreme challenges. In American city neighborhoods that have seen racial and ethnic demographic changes over the last century, Jewish synagogues have been frequently converted into Baptist and AME Churches. In the past quarter century or so, there have also been many successful mill conversion projects in the Northeast and other parts of the country. The Tate Modern in London is an example of adaptive reuse at the urban scale - converting an old power plant along the River Thames into a Gallery of Modern Art - and also an example of urban renewal. Station Square in Pittsburgh Pennsylvania is an example of a mile-long former Pittsburgh and Lake Erie Railroad terminal and headquarters being converted into a retail, office, hotel, and tourist destination.

Other museums adapted from old factories include "MassMOCA" - the Massachusetts Museum of Contemporary Art, the Center in Long Island, New York and - The Dia Art Foundation Museum in upstate New York.

In San Diego, California, the historic brick structure of the Western Metal Supply Co. building at 7th Avenue (between K and L Streets) was preserved and incorporated into the design of PETCO Park, the new baseball-only ballpark of the San Diego Padres, and can be prominently seen in the left-field corner of that ballpark. It now houses the team's flagship gift shop, luxury rental suites, a restaurant and rooftop bleachers, and its southeast corner serves as the ballpark's left field foul pole.

In Europe, buildings originally constructed as royal palaces are often reused as art museums; well-known examples of this being the Louvre in Paris, France, and the Winter Palace in St Petersburg.

Adaptive reuse is also related to the field of historic preservation.

External references

• On Adaptive Reuse A blog, mostly architectural, but it also treats adaptive reuse as an approach to a wide range issues.
• The Institute for Adaptive Reuse, Washington D.C.
• "Adaptive Re-Use of Brownfields: A Challenge for the Valuation," John A. Kilpatrick