In addition to the 574,283 resident Bostonians spread throughout sixteen different neighborhoods, the city's weekday daytime population literally doubles each morning as job commuters, travelers, shoppers, and those taking advantage of the city's services and cultural activities all pour into Boston to add to the city's already lively mix. Compared to city residents, of course, those entering the city during the day to work or use services tend to be higher income, whiter, and younger than today's Bostonians themselves. One group that has brought vitality to Boston's social life are the 134,796 students at the city's 32 different colleges and universities. More than 90,000 of these live in Boston itself, making up more than one of every six residents. Half again this number, like so many of the city's workers, are commuters.

The 1980s saw many changes in population and many new residents, such that the typical city resident was a relative newcomer, living in the city less than five years. By the late 1990s, migrations to the city began to outnumber losses, and Boston began to gain population again after a long decline that began in the 1950s. The 1990's saw both many "new immigrants" and new professional workers move here. As of 2000, for the first time in the city's history, "whites" are also now in the minority in Boston, at 49.5% of the population. The city is now almost one fourth African American, 15% Latino, and 8% Asian-Pacific Islander.

Long thought to be a collection of separated, culturally homogenous "ethnic villages", Boston today shows its dramatic diversity in almost every neighborhood. Each one of Boston's sixteen neighborhood districts is more diverse in 2000 than in 1990. Latinos and Asians have moved into every neighborhood, and formerly mostly white and mostly black neighborhoods are now more racially mixed than before. Even among the city's recently traditional "white" neighborhoods, none is more than 85% so (Back Bay/Beacon Hill at 85%, West Roxbury at 84%, South Boston at 85%, and Charlestown, 79%). Except for Mattapan, which is still three fourths African American, "minority" neighborhoods tend to be more integrated than whiter ones. One third of those who call Roxbury home, for example, now identify themselves as belonging to groups other than African-American. Central Boston, with Chinatown, is 21% Asian, but Asians also make up one of seven residents in Allston-Brighton, North Dorchester, and Fenway/Kenmore. Latinos are a strong presence in East Boston, where they are two of every five residents, and are one in four in Roxbury and Jamaica Plain, and almost one in five in the South End and Roslindale. The typical Boston neighborhood in 2001 is an integrated one, with these six being the most equally balanced in their populations: South End, Dorchester, Hyde Park, Jamaica Plain, East Boston, and Roslindale.