Cities have historically been powerfully shaped by the development of key infrastructural technologies. Complex socio-technical systems of water, energy, transport, communications and waste make the concept of the contemporary city possible (Graham and Marvin, 1996, 2001). While there have been dramatic changes in the social organization of infrastructure and drivers shaping its development, the physical infrastructure of the city is often slow to change. Cities face the challenge of shaping complex technological transitions – refitting new and often hybrid energy infrastructures, laying new ICT systems over old infrastructures, through road pricing and control technologies, introducing decentralized new and renewable technologies into centralized systems (see Graham and Marvin, 1996; Guy and Marvin, 2001; Guy et al, 2001). Yet we lack a systemic way of understanding the role of places in shaping such socio-technical transitions (Eames et al, 2006; Hodson and Marvin, 2006).