We document and then develop a model explaining and relating changes in firms'' organisation and in urban structure. Sharing of business services by headquarters and of sector-specific intermediates by production plants within a city reduces costs, while congestion increases with city size. A...

Why are some cities specialised and others diversified? What are the advantages and disadvantages of urban specialisation and diversity? To what extent does the structure of cities, and the activities of the firms and people in them, change over time? How does the sectoral composition of cities...

London is one of the world’s major cities, and one of its most diverse. London’s cultural diversity is widely seen as a social asset, but there is little hard evidence on its importance for the city’s businesses. Theory and evidence suggest various links between urban cultural diversity...

The digital industries cluster known as 'Silicon Roundabout' has been quietly growing in East London since the 1990s. Now rebranded 'Tech City', it is now the focus of huge public and government attention. National and local policymakers wish to accelerate the local area's development: such...

This paper reviews a growing literature investigating how ‘immigrant’ diversity relates to urban economic performance. As distinct from the labor-supply focus of much of the economics of immigration, this paper reviews work that examines how growing heterogeneity in the composition of the...

This paper investigates how physical, organisational, institutional, cognitive, social, and ethnic proximities between inventors shape their collaboration decisions. Using a new panel of UK inventors and a novel identification strategy, this paper systematically explores the net effects of all...

Growing cultural diversity is seen as important for innovation. Research has focused on two potential mechanisms: a firm effect, with diversity at the firm level improving knowledge sourcing or ideas generation, and a city effect, where diverse cities helping firms innovate. This paper uses a...