The basic purpose of the research was to describe the world city network through the location policies of global service firms. The office locations (and their importance) were collected for 100 business service firms (18 accountancy, 15 advertising, 23 banking/finance, 16 law, 11 insurance, 17 management consultancy). From the resulting data matrix, various data reduction and connectivity matrices were derived to describe the basic configuration of the world city network. The basic matrix consists of 316 cities for which 'service scores' are provided, describing their importance to the servicing activities of 100 service firms. Scores range from 0 (no presence of a firm in a city) to 5 (headquarters of a firm in a city).