A smart city (also smarter city) uses digital technologies to enhance performance and wellbeing, to reduce costs and resource consumption, and to engage more effectively and actively with its citizens. Key ‘smart’ sectors include transport, energy, health care, water and waste. A smart city should be able to respond faster to city and global challenges than one with a simple ‘transactional’ relationship with its citizens. Other terms that have been used for similar concepts include ‘cyberville, ‘digital city’’, ‘electronic communities’, ‘flexicity’, ‘information city’, ‘intelligent city’, ‘knowledge-based city, ‘MESH city’, ‘telecity, ‘teletopia’’, ‘Ubiquitous city’, ‘wired city’. Interest in smart cities is motivated by major challenges, including climate change, economic restructuring, the move to online retail and entertainment, ageing populations, and pressures on public finances. The European Union (EU) has devoted constant efforts to devising a strategy for achieving ‘smart’ urban growth for its metropolitan city-regions. Arup estimates that the global market for smart urban services will be $400 billion per annum by 2020. Notably ‘smart’ cities include Chicago, Boston, Barcelona and Stockholm.