In this paper we summarize and comment on the papers published in issue 6.3. The papers reviewed are: 'In Search of "W"' by Richard Harris, John Moffat & Victoria Kravtsova; 'Cross-national Neighbouring Effects on European Regional Specialization' by Toni Mora, Patricia Garcia-Duran & Montserrat Millet; 'Intra-national Purchasing Power Parity and Balassa- Samuelson Effects in Italy' by Andrea Vaona; 'Enterprise and Competitive Advantage in the Australian Context: A Spatial Econometric Perspective' by Paul Plummer & Michael Taylor; and 'Development of a Large-scale Single US Region CGE Model using IMPLAN Data: A Los Angeles County Example with a Productivity Shock Application' by James Andrew Giesecke.