This introductory chapter identifies the characteristics of tourism cities and world tourism cities and provides clear definitions of the two terms. Eight criteria that underpin tourism cities are identified. World tourism cities are described as transport gateways and as influential, impactful, cosmopolitan and recognised. They are also places that have great concern for the sustainable development of tourism. Examples are provided so that readers have a clear understanding of world tourism cities.

Recognition is one of the factors that defines a world tourism city. As such, the concept of a World Heritage (List) city via UNESCO designation is also reviewed, as is UNESCO's Creative Cities Network (UCCN). Cities also receive recognition from the media and other sources including travel magazines. Social media customer engagement is specified as a further indicator of recognition.

There is no universal consensus on which urban areas are world tourism cities (or even tourism cities). So, the relevance and roles of various city rating schemes are considered. These systems produce results that often do not match as the criteria applied are dissimilar.

Several organisations representing tourism cities are profiled. One of these is the World Tourism Cities Federation (WTCF) based in Beijing and another is European Cities Marketing with its offices in Dijon, France.