THE "friendliness" of a city is not an easy thing to measure. Yet, even if intangible, it may still be of decisive importance - especially for a vigorously globalizing urban giant, whose skyrocketing economy relies on huge inflows of overseas talent, investment and tourism.

The prominence of this issue to Shanghai is reflected by a standard sentence, encountered repeatedly on relevant Websites and promotional materials: "In building Shanghai into an international metropolis the open-minded, cheerful and hospital [sic] Shanghai people warmly welcome visitors from all places in China and the world."

This spirit of openness seems to be sincerely embraced by the vast majority of Shanghainese, who have seized upon the era of "reform and opening up" as an opportunity to restore the dazzling international reputation their city established in the early 20th century.

Many even make comparisons with the flourishing cosmopolitan civilization of the Tang Dynasty (618-907) and Song Dynasty (960-1279) when national self-confidence, trade, exploration and cultural exchange were climbing towards a historical zenith, before degenerating into the narrow-minded inwardness of the later dynasties.

Indeed, as a vast country with an even vaster population, boasting an ancient, vibrant and sophisticated culture, China has often found it difficult to maintain its balance in respect to foreign influences. Throughout its long history, creative pride in its astonishing achievements has often toppled over into destructive arrogance, conservatism or complacency, severely retarding the country's development over the last half-millennium.

From the perspective of most foreign visitors today, the determination of Shanghainese to both widen and deepen their engagement with the world is an evident and delightful fact, inextricably bound to the city's breath-taking renaissance as an international hub and economic magnet.

For native English speakers, the eagerness of locals to practise the language has a significant effect on their social interactions. Bob, a long-term expatriate from the UK working for a local company, remarked: "People here are very friendly and keen to communicate, but it can get too much sometimes. In Beijing I felt I was being swallowed alive at times. Shanghainese are a bit 'cooler' - a bit more restrained about approaching strangers for on-the-spot English lessons."

The difference is one of degree. "English Corners" - where native speakers chat to locals in English about every topic under the sun - are held regularly at locations throughout the city, reliably attracting dense and enthusiastic throngs. Foreigners attending such events can feel overwhelmed at first, but the warmth and interest of the locals are unmistakable.

The city's general level of English competence can come as quite a surprise to those who know how recently it has re-opened to the world.

Jim, a recently arrived expat from the US remarked: "What shocked me was that waiters here will sometimes apologize for their weak English, as if mastery of a foreign language was something you would expect. I tell them I'm impressed they're making the effort at all. It makes me even more ashamed of my crummy Mandarin."

Small ads in the city's newspapers are cluttered with appeals for language exchanges, not only with native English speakers, but also for those of other major regional and international languages.

The inevitable economic squalls and dislocations of an uncertain world may complicate the city's recent unambiguous advances, but Shanghai's cosmopolitan history and populace mean it will probably cling resolutely to its current path. After all, Shanghainese seem to enjoy sharing their city with the world.

Whatever the future may bring, today Shanghai's eyes, ears and arms are wide open, and its appreciative foreign visitors, whether long- or short-term, are united in hoping it remains so.