As he shakes hands, poses for pictures and cracks wise over the course of cocktails, dinner and a post-banquet party, no opportunity is missed to remind people that he is the best - and most in-demand - photographer in the fickle world of fashion. Arrogant-sounding words, granted, but with the arrogance diluted somewhat by trademark Testino shrugs and smiles.

This three-day series of parties marking China's seventh anniversary, and attended by all the bigwigs from all the major fashion houses, offers a golden chance to catch up with long-standing contacts and tap potential clients in the fast growing mainland luxury market.

Testino did not get to the top of the fashion-photography pile and become lodged there, seemingly immovable, by being lackadaisical about business and cultivating allies, nor indeed by trying to be too radical or avant garde. Although his work invariably involves the creation of beautiful, often ethereal, images, contract negotiation is another matter altogether: Testino is an unapologetic pragmatist, who fully understands the relationship between fashion brands and the magazines that display their wares.

In short, commercial appeal to the maximum number of people is always the priority: editors and advertisers who want a mean and moody production from a temperamental artiste are unlikely to book Testino, whose oeuvre is generally smiley, colourful and upbeat.

A bit like the man himself. The Peruvian exudes a South American warmth and charm mixed with a wry humour acquired from having lived in England for more than 30 years. During that time Testino has risen through the ranks, starting with teen magazines then graduating to designer labels and working with Madonna before crowning his renown with candid and charming images of a joyful-seeming Princess Diana taken just months before she died, in 1997.

From there on, Testino's career went into overdrive. Among the luminaries he has shot over the past decade are David Beckham, Margaret Thatcher, Lady Gaga, Elton John, Jennifer Lopez, George Michael and Brad Pitt. More recently, Chinese socialites and movie stars, including Fan Bingbing and Hong Kong actor Daniel Wu Yin-cho, lined up before the Testino lens for an American shoot.

with very open eyes, a very positive eye and I find that this is a magnificent country when you look at the history," says Testino. "The influence of Asian culture this season is unbelievable; everyone is interested in Asian culture.

"I have a lot to learn about China and coming here several times recently has helped me gain an understanding. You can't learn it overnight and I really need to know more. How do you get the business if you don't know what you are catering for?

"You have to know the culture. I need to come here and see the real Chinese and get in tune with the country and the tastes of its women. For instance, the French woman would not want to be eccentric, like the English one, with colour and prints; she wants to be chic in black. Whereas the American woman always wants to be comfortable."

The process of learning about China has been aided by Hong Kong textile tycoon Silas Chou, known for throwing elaborate penthouse parties for fashion-world worthies passing through town. At one such gathering, Testino met executives of Chinese brand Ochirly, who promptly commissioned him.

On a subsequent visit, for the Beijing opening of "Private View", an exhibition of images taken by Testino that has since moved on to Shanghai, the snapper was feted by the city's high society and, once again, expanded an already bulging contacts book. It's a far cry from Testino's first visit to the country, as a photographer for magazine shooting fashion pictures in the karst mountains of Guilin.

Testino recalls the shoot vividly. "It was a six-hour ride back from where we were shooting and we hadn't seen a car for two hours," he says. "We saw this gorgeous rice paddy that I wanted to shoot and there was a phone wire right in front of where I wanted to do the picture. I was wondering what to do and suddenly a car approached. It was telephone engineers who had come to change that particular line. They took the wire down, I took my picture and then they put it up again.

"It was weird and amazing. Things like that happen to me. In a funny way my whole life has been like that, made of opportunities that came about because of my curiosity.

"Originally, when I went to London, I wanted to go into communications and I met a girl who was at photography school and I joined the school to get my visa. In Peru at that time, in 1976, there wasn't a possibility for a career in photography, never mind fashion photography. There wasn't even a designer in Peru, so how could there be a fashion photographer? The career in photography really came about by accident. Everything that has happened since then, it is almost as if someone wanted it for me rather than it being me who wanted it."

That invisible power, divine or otherwise, has inves-ted Testino with star wattage - he is a celebrity who when boarding a plane instinctively veers left, to the first-class compartment, and hangs out with the famous names he shoots. Supermodel Kate Moss is a long-term muse and friend, and the subject of one of his 11 books and numerous magazine covers.

Testino is the undisputed top dog of fashion photography, an individual who in 2010 notched up 10 of American 's 12 covers. Does he worry about younger talent snapping away at his heels? Not much, it would seem.

"I believe nothing should last forever," he says. "I am excited at the new talent and what I will do at my level later. I always say about women that it is pointless trying to stay young. I see these women who are 60 with their face lifted, their hair dyed, mini-skirt and high boots, trying to look 30. I think they will never look better than a 30-year-old woman, so why fight it? Why not go the other direction and embrace your moment? I am not trying to become 18, I am establishment and I am 58. I don't want to do the weird picture I did 20 years ago. I want to do a picture that will last."

pictures showed the British princess as radiant, happy and fun, seemingly delighted to be involved in a fashion-magazine photo session. The shoot, for Vanity Fair, was widely interpreted as a statement of intent by Diana - the start of a new, more independent life, away from the stifling protocol of Buckingham Palace. They acquired a certain poignancy when the princess died with her lover, Dodi Fayed, in a car crash in Paris just months after they were published.

Testino's connections with the royal family did not end there. He has since shot portraits of a relaxed Prince Charles with sons William and Harry, and he took the engagement photographs of Prince William and Kate Middleton.

There is one prominent royal missing from the Testino portfolio: Queen Elizabeth. Despite Testino's work with her son and grandsons, when it came to shooting her formal portraits, the monarch chose American photographer Annie Leibovitz. Mention of this scoop is one of the few occasions when a frown flits across Testino's brow.

"I don't see her as a rival because I am a fashion photographer by nature and she is not, she is a portraitist," he says, before embarking on further royal recollections.

"I photographed the queen only once, as a paparazzi of sorts. I was allowed to document a night [in 2002 at London's Covent Garden] opera house [at an event to mark her 50th] jubilee and I was not allowed to talk to her, or be introduced to her. But there is an image where she is looking at the camera and you would think she was my best friend forever.

"My first picture of the royals was at the procession of carriages going to Diana and Charles' wedding, when I was a nobody. I was sitting on top of a mail box and I photographed the Queen Mother in a carriage with Prince Edward: she is looking at the camera as if it was me she was looking at."

Testino currently has a show of royal pictures in London, as well as "Private View" in Shanghai, which covers a broader spectrum. Already, he is talking about returning to work in China, assuming a slot can be found in a schedule that is planned months ahead and involves pinballing around the planet.

London is nominally home - "the British trained me, educated me and I have tried to emulate them" - but for much of the year, Testino lives out of a hotel suite, checking in, shooting photographs, partying hard and meeting clients.

such as film stars Maggie Cheung Man-yuk and Zhou Xun, and designers Jason Wu, Phillip Lim, Andrew Gn and Vivienne Tam, the photographer is in his element. The American ambassador's wife, Mona Locke, is given the full charm offensive, as are two up and coming young Chinese designers, who shyly approach Testino to express their admiration. The photographer does not fully catch their names, only the gist of their introductions; but they are immediately targeted as future clients. "Don't forget, when you have your own design house, give me a call and I will shoot the pictures. We can both make money!"

And with contacts made, he heads off to the Park Hyatt nightclub, trailing a gaggle of jewel-bedecked pretty young things in his wake.

CLOSE-UP

Put Mario Testino near a camera - any camera - and he cannot resist giving directions; advising on the light, the pose and the aperture.

This picture, shot in the photographer's suite at the Park Hyatt in Beijing, shows him bathed in the blind-filtered late afternoon light of the city. The close-up depicts the creases and lines of a relaxed 58-year-old in a comfortable cardigan, the opposite of the kind of pictures Testino is famed for, which invariably show beautiful young women in fabulous clothes.

For many of those images, Testino uses a standard 50mm lens, the kind found on most amateur digital cameras. In fact the photographer is something of a happy-snapper himself, and always carries a pocket-sized camera to take pictures at dinner or on the dance floor.

Although, like many professionals, he makes it look easy, in reality, his technique took years to refine.

"Hard work is always needed," he says. "You need to be prepared for it. Never give up, fight for your ideas, listen to the people you respect, surround yourself with people who are more talented than you, be surprising, make people have a good time and pray the clients like it!

"I work very closely with my stylists and fashion editors. They are the ones that take me by the hand and make sure I do it right. I then work with the set designer and we decide what we will do. I will choose the model with the fashion editor and once we are on the shoot we will look at all the clothes and I will sit with the hair and make-up artist to work on the look together.

"I will also work with the assistants to get the lighting right and then we'll be ready to take the picture. At that point I need to work with the model to bring the best out of her and create the picture. The whole process is very collaborative."