1. A brownfield deployment, in information technology, is the installation and configuration of new hardware or software that must coexist with legacy IT systems. A greenfield deployment, in contrast, is the installation and configuration of software or hardware that a company has not used before and is not dependent upon legacy technology.
The terms brownfield and greenfield come from the building industry, where previously developed land is described as being brownfield and previously undeveloped land is described as being greenfield. In information technology, as with construction, brownfield deployments can be cost-effective because the infrastructure to support the new installation is likely to be already in place. However, brownfield deployments can be complicated by the need to rectify dependencies between the new and current installations.
2. In construction, a brownfield site is land that was previously used for industrial purposes. Examples of brownfield sites include abandoned factories, gas stations that have gone out of business or empty strip malls. Brownfield redevelopment can be cost-effective because access roads, sewer, water and perhaps even buildings are already in place. Brownfield site redevelopment can be complicated, however, by the presence of hazardous substances, pollutants or contaminants left behind by the previous tenant.