ABSTRACT
The interest in the role of cities in explaining national economic performance is not at all
new and has always been at the basis of urban economics theory and economic geography
studies. In the 1990s, thanks to seminal contributions (Glaeser et al., 1992; Krugman,
1991), a resurgence of interest in cities and in their role in national economic performance
was registered, followed by more recent studies, especially on the North American reality
(Glaeser, 2008; Henderson, 1974, 1985, 1996; Rosenthal & Strange, 2004; Sassen, 2002;
Scott, 2001).
