The process of wealthier residents moving to an area, and the changes that occur due to the influx of wealth. As wealthier inhabitants move into an area that is already populated with lower-income residents, the neighborhood begins to change as well. Often this will spark an urban renewal process, which cleans up the town, but often leads to an increase in rent, taxes, and other items. Sometimes this change means that the previous residents can no longer afford to live in that neighborhood, which is why gentrification can sometimes be used in a negative context. However, many good changes also historically accompany gentrification, such as decreased crime rates and increased economic activity.