The section on the localization thesis draws on a paper written by Ash Amin with Anders Malmberg. We are grateful to Anders for allowing us to use some of the material. The section on Santa Croce is based on research funded by the Nuffield Foundation. Special thanks are due to Fabio and Anna Sforzi, without whose contacts, support and research input the project would not have taken place. The section on the City of London is based on work with Andrew Leyshon. Useful comments were received from Neill Marshall, Diane Perrons and two anonymous referees. Both authors also wish to acknowledge the support of the European Science Foundation's research programme on Regional and Urban Restructuring in Europe (RURE). It is their membership of the programme which gave rise to this paper.