Luxury: How to sleep with Mr Armani

"Mr Armani will be here any minute... I think I can hear him," whispers one member of the immaculately Armani-suited Swat team of PR people, translators and personal assistants nervously straining their ears towards the door of the Italian fashion designer's private office at the heart of the Armani empire in Milan.

Like patient courtiers, we have been waiting for a glimpse of the king of the deconstructed suit for what seems like hours. The office itself is arranged with the fanatical precision of a luxury prison cell: everything down to the last doorknob is a master class in obsessively discreet, sophisticated understatement. Shafts of cold winter sunshine bounce off a gleaming glass desk, on which every perfectly square paperweight, notebook and lamp sits at neat perpendicular angles to the edges.

A layer of nervous perspiration gleams on the forehead of the photographer, who has been fiercely instructed that Mr Armani must be shot only with a dark background ("to preserve the definition of his white hair"), from the left side ("his best side") and with minimal lighting ("to prevent shine").

As the ambassador of one of the world's most successful fashion brands, Mr Armani leaves nothing to chance, spending an hour with his personal trainer in his private gym every morning, and carefully moderating his intake of food and wine (which, I am told, he very rarely drinks). He clearly runs a tight ship – in body and mind as well as business.

We have already been treated to a drive in the Armani Mercedes, toured the complex of Armani stores and Armani offices, and eaten exquisite white-truffle pasta at the Armani Caffé on Via Manzoni. Now, it seems perfectly plausible that, like some minor envoys to the court of Louis XVI, we could take up residence here for years without ever getting to actually meet the monarch.

Then suddenly he is here, with a couple of decisive strides across the room in a flash of white teeth and midnight-blue cashmere, and a crinkly half-grin. "Ciao," he says, energetically pumping my hand in one bronzed paw, while muttering orders in Italian to the bevy of staff buzzing around. Expensively tanned, with the short limbs and tightly wound frame of a Staffordshire bull terrier, this 73-year-old is the living embodiment of the fashion brand's billion-dollar formula.

As he sits, poised on his chrome-and-leather throne, he explains that his perfectionism comes from a lifelong sense of dissatisfaction with the world, stemming from his childhood growing up in Piacenza in northern Italy during the war. "It was a pretty basic, circumscribed environment that I grew up in, so I had ample scope to see things I didn't like. From an early age I used to look for something different from what was before my eyes, so I suppose some of it derives from discontent with what I saw." One hand reaches across the desk to reposition his lamp that all-important 5mm to the left.

Attention to detail features prominently in the Armani aesthetic. As a child he would make dolls out of mud and then dissect them with a knife, giving himself marks out of 10 for accuracy. He later spent three years studying medicine at university in Piacenza.

Today, Armani's quest for what he calls "a certain refinement, an aesthetic milestone" has transformed the small fashion label he started in 1974 with Sergio Galeotti into a fashion empire with 5,000 employees worldwide and an annual turnover of $2bn. And it doesn't end with suits: Giorgio Armani has brought his aesthetic vision to the home and lifestyle market with Armani Casa, Armani Cosmetics, fragrances, watches, restaurants, a bookshop and a nightclub – and he has now signed a contract to create 14 Armani Hotel & Resorts in locations worldwide. He calls it "a process of osmosis", adding, "Today, people want a designer who is thought to be a person of taste and genius to give them pointers in everything – from what to wear, to choosing something for the home, to their choice of holiday destination."

The brand inspires an almost evangelical devotion among its staff. Employees are paid a good wage, receive an annual clothing allowance and a generous discount – and everyone from courier to concierge is dressed head to toe in Armani. They call it the "black hole", because once you are in, you never want to leave – and the same is true of some of the brand's clientele. Where Giorgio goes, they will follow – which is precisely the concept behind the extension into hotels, custom-built to further attract wealthy pleasure-seekers and business people from around the world to the tax-free desert honey pot of Dubai.

On Armani's desk there proudly sits an intricate glass model of the Burj Dubai, which, when it is completed later this year, will be both the tallest building in the world and the site of the first Armani Hotel. For this project, Giorgio Armani has designed 160 guest rooms and 144 bespoke luxury residential apartments. It seems a fitting collaboration; Armani agrees: "What these worlds share is an ultra- glamorous, ultra-spectacular, ultra-luxurious aesthetic."

Using precisely the same eye for simple details that revolutionised the traditional Savile Row suit – softening shoulders, dispensing with lining – he claims to have honed and modernised the gratuitous impracticality of the traditional luxury hotel with "comfort, serenity and sensuality through... use of colour and materials".

"Hotels are often ostentatiously luxurious – yet fail to provide a drawer for your shirts," he says. "I was once in a hotel in Shanghai where there were 1,000 cushions on the bed, but no small stool to sit on in the bathroom to dry one's feet – which is why I chose to furnish the Dubai hotel and residences in a style I have always loved for a home."

Of course, it is as impossible to imagine Mr Armani drying his own feet as it is to imagine the Queen shaving her legs. But this is the secret of the Armani formula: the man has forged his empire on the smooth surface of impenetrability that sweeps across every product line, from the suit that creates strength where there was once weakness, to the bedroom suite that creates order where there was once disorder. Every seamless, steely grey surface in the Armani Casa range is an implacable example of the premium the designer places on discretion above all else.

When I ask how he maintains privacy, particularly in the 21st-century celebrity world of crotch shots and kiss and tells, he replies, "I have always applied discipline to work and to my private life, so it has not been too difficult. If I were a person with a very complex personal life, it would be much more difficult to maintain a discreet professional image."

It was this combination of mystery and glamour that won Armani a permanent place in the wardrobe of the Hollywood elite, ever since Richard Gere first brought the deconstructed suit to the silver screen in the 1980 film American Gigolo. Quick to realise the promotional value of A-list endorsement, in 1983 Armani was the first designer to open a Hollywood office dedicated to attracting celebrities, and now counts Arnold Schwarzenegger, Samuel L Jackson, Kevin Spacey, Sophia Loren, Sean Connery, Jodie Foster and Michelle Pfeiffer among his fans. Not only does he dress the world's most glamorous Hollywood icons, but by virtue of his reputation he has joined their exclusive club. And he has a Warhol portrait of himself propped against a wall in his office to prove it. But, he says smiling, "The fact of being an icon only occurs to me, and only enters my life, on rare occasions. It's very challenging when you walk around the streets or go to the cinema or a restaurant and people are always looking at you, and it tends to detract from the pleasure of behaving naturally and just being a human being. When I do feel myself to be an icon, I play the role accordingly – but when I come back here, the icon has vanished."

The designer remains uncompromisingly private on the matter of his personal life. He is endlessly articulate on the subjects of his design philosophy and his business, but ask him about holidays, favourite pasta dishes, friends, boyfriends or what makes him laugh and cry, and the shutters come down.

Home for Giorgio Armani is a large Milan palazzo in the same grand building as the theatre he has used to stage catwalk shows for the past 20 years. Below the catwalk is the swimming pool Armani does his laps in every morning. Inside the apartment, he holds the occasional private dinner party for close friends (Eric Clapton, Robert De Niro, Leonardo DiCaprio, Ricky Martin, to name a few) and every Thursday he attends his nightclub, Armani Privé, and has dinner at the Armani Nobu restaurant, co-owned by De Niro. In other words, Armani lives, breathes, eats and swims in the brand he has created. He has built a lavishly understated ' Never-Never-Land for grown-ups in which he can promote and live out his design concept – without ever having to let the humdrum imperfections of everyday life interfere.

Perhaps this is why "home" is such an important concept to the designer, because it is the place where "one is insulated from the world, protected from the outside. You must create your own world. Then," he says, "you can live your most personal moments in a highly intimate environment which delights and enfolds you."

Armani owns houses all over the world – from his favourite villa on the volcanic island of Pantelleria near Sicily, to Broni in Lombardy, St Tropez, St Moritz, Paris, New York and Antigua – as well as the new Armani yacht Marmania, which is due to set sail this summer. "I spend most of my holidays in one of my houses, but I appreciate that it is important, occasionally, to get away from your own setting and to appreciate the world outside."

As mass brands embrace every corner of the globe – from clothes to interiors and tourism – does this pioneer of the branded lifestyle see luxury travel going the same way? "People love to travel more than ever," he says, "but they also like to find a congenial environment when away from home. In the past, the only people who travelled were those with an innate love of travel, whereas today travel has become an indispensable means of familiarising oneself with the world around us, because television and other media have brought everything so much closer to us." In other words, as the branded world closes in, via PC screens and cheap flights, people driven by newfound aspirations will increasingly be able to experience the same luxury touchpoints everywhere in the world, from Marrakech to Mumbai. Spending a night in an Armani suite could soon be as easy as picking up a Chanel lipstick at the airport.

But the future is a potentially thorny issue for this sole owner of one of the biggest fashion empires in the world. He has a fabulous pair of pecs, works a gruelling schedule, personally oversees the design of every pair of jeans, footstool and pair of boxer shorts that goes into production and has been famously quoted as saying, "My life is my work, my work is my life". Surely he can't go on forever?

"As someone of a certain age, this is always on my mind; I think that is quite normal," says Armani contemplatively, and it must, indeed, be a strangely disembodying sensation to think about the immortal nature of the empire he has created, guaranteed to continue long after he is gone – let alone the possibility of a successor.

"I am always aware of previous examples of the past, remarkable names that have disappeared, and withoutthe founder everything has changed. Fashion houses, in particular, are affected and this makes me ponder, very deeply, what will happen in the post-Armani era. On a business level it is obvious that I must concern myself with endeavouring to construct teams of people able to take over responsibility, and to whom I can entrust the task of managing Giorgio Armani throughout the world in the future. But on a personal level, I prefer not to think about it, as I would rather work day to day as if starting my life anew every 24 hours."

This is the first time the Herculean fashion icon has revealed even a glimpse of the man beneath the slick exterior. He continues: "When three-quarters of your life have passed, every day you live is a gift to yourself; I don't wish for anything more than to live the rest of my life each day as it comes."

As I get up to leave, Armani springs to his feet, tells me I have "lovely eyes" and demands that we have a photograph taken together. Briefly, the icon vanishes and there emerges the man from a small town in northern Italy who, in another life, might have been a doctor, lawyer, film director or writer. "But definitely something creative," he exclaims with a final crinkly half-smile.