The 2008 Nobel prize for economics was awarded to Paul Krugman for three papers - Krugman (1979, 1980, 1991). In this paper we illustrate that, indeed, these three papers are closely connected. We present - a summary of - the papers using a unified framework. Central in the discussion is the...

Economic activity tends to cluster. This results in productivity gains. For policy makers this offers an opportunity to formulate and promote policies that foster clustering of economic activity. Paradoxically, although agglomeration rents are often found in empirical research a rationale for...