Urban Planning: Planning In a Globalised World

The Global City: Introducing a Concept - Saskia Sassen

The chapter by Sassen on global cities discusses what specifically defines a global city and how these features of global cities work. She outlines 7 main hypotheses for the global city model, in summary they are;

1. Geographic location and distribution; where the more dispersed the more complex a firms functions are.
2. Firms outsource their functions to other service firms, for example; accounting, public relations etc.
3. Agglomeration economics; service groups are involved together: ‘mix of firms, talents, and expertise form a broad range of specialised fields makes a certain type of urban environment function as an information centre.
4. Signficant amount of heatquarters of firms
5. Provides a global service or a partnership which strengthens cross border transactions and networks
6. The amount of professionals and proven talent
7. Firms that need to operate- society, businesses and economies need their services

Evidently from these hypotheses, technology and the existence of transnational corporations define global cities. The growth of networks between global cities is dependent on political, cultural, social and criminal factors. The article then goes on to discuss worldwide networks and central command functions, and expands on the importance of headquarters in global cities as well as stock markets, agglomeration economics and trade.

The next section discusses the impacts of new communication technologies on centrality. There is three assumed points about centrality and technology. Firstly there is no longer a distinct correlation between centrality and geographical centres like CBDs and downtown. Second, the centre can extend to form a grid due to expansion like in Paris and third, these centres are fundamental to economic and trading. Other than these listed above, technological communications may also cause inequality between global cities where there are larger economic and social structures. 

The final section discusses the global city as a centre of political power, and when this centre does not possess official political power, corporations hold an even greater power.