The catalyst in both cases was a major civic investment. One was the building of Lincoln Center in the early 60 s, and the multitude of entertainment, sports and cultural venues that were supplied to Baltimore Harbor. But in both, as well as in other cities, it was an expensive proposition and the results were slow to take hold. So there haven t been many induced gentrifications. Examples of spontaneous ones however, are legion.
Spontaneous gentrification takes off without municipal intervention.
South Florida, in just twenty years, has witnessed the gentrification of Coconut Grove, Miami Beach, and the scrappy old town of Key West. As it happens, all of these transformations were driven by individuals discovering the excellent urban qualities of each place. The government caught up later to take credit, and to interfere with the natural cycle, for better or worse. The process of spontaneous gentrification begins surreptitiously, when a first wave of the poor but savvy discover the urban quality of a hitherto decrepit area. These are usually students, artists, perhaps gays, and other self-marginalized social groups.