A. ALPHA WORLD CITIES (full service world cities)
12: London, New York, Paris, Tokyo
10: Chicago, Frankfurt, Hong Kong, Los Angeles, Milan, Singapore
B. BETA WORLD CITIES (major world cities)
9: San Francisco, Sydney, Toronto, Zurich
8: Brussels, Madrid, Mexico City, Sao Paulo
7: Moscow, Seoul
C. GAMMA WORLD CITIES (minor world cities)
6: Amsterdam, Boston, Caracas, Dallas, D�sseldorf, Geneva, Houston, Jakarta, Johannesburg, Melbourne, Osaka, Prague, Santiago, Taipei, Washington
5: Bangkok, Beijing, Montreal, Rome, Stockholm, Warsaw
4: Atlanta, Barcelona, Berlin, Budapest, Buenos Aires, Copenhagen, Hamburg, Istanbul, Kuala Lumpur, Manila, Miami, Minneapolis, Munich, Shanghai
