The gentrification process is typically the result of increasing attraction to an area by people with higher incomes spilling over from neighboring cities or towns. Early "gentrifiers" may belong to low-income artist or bohemian communities, which increase the attractiveness and flair of a certain quarter. Further steps are increased investments in a community and the related infrastructure by real estate development businesses, local government, or community activists and resulting economic development, increased attraction of business, and lower crime rates. In addition to these potential benefits, gentrification can lead to population migration and displacement. However, some view the fear of displacement, which is dominating the debate about gentrification, as hindering discussion about genuine progressive approaches to distribute the benefits of urban redevelopment strategies.
Historians say that gentrification took place in ancient Rome and in Roman Britain, where large villas were replacing small shops by the 3rd century, AD. The word gentrification derives from gentry—which comes from the Old French word genterise, "of gentle birth" (14th century) and "people of gentle birth" (16th century). In England, Landed gentry denoted the social class, consisting of gentlemen. British sociologist Ruth Glass coined the term "gentrification" in 1964 to describe the influx of middle-class people displacing lower-class worker residents in urban neighborhoods; her example was London, and its working-class districts such as Islington:
One by one, many of the working class neighbourhoods of London have been invaded by the middle-classes—upper and lower. Shabby, modest mews and cottages—two rooms up and two down—have been taken over, when their leases have expired, and have become elegant, expensive residences ... Once this process of 'gentrification' starts in a district it goes on rapidly, until all or most of the original working-class occupiers are displaced and the whole social character of the district is changed.
In the US, the Centers for Disease Control and Prevention report Health Effects of Gentrification defines the real estate concept of gentrification as "the transformation of neighborhoods from low value to high value. This change has the potential to cause displacement of long-time residents and businesses ... when long-time or original neighborhood residents move from a gentrified area because of higher rents, mortgages, and property taxes. Gentrification is a housing, economic, and health issue that affects a community's history and culture and reduces social capital. It often shifts a neighborhood's characteristics, e.g., racial-ethnic composition and household income, by adding new stores and resources in previously run-down neighborhoods."