One step ahead: An exclusive behind-the-scenes look at what makes Prada the world's most influential fashion label

From simple nylon rucksacks to wilfully challenging shoes, one label has always been at fashion's cutting edge. And that's to say nothing of the yachts, architecture, art patronage... Now a new book lays bare the full extent of the empire that Miuccia Prada has built, and the extraordinary influence her designs have over us

Careful observation of and curiosity about the world, society and culture are the core of Prada's creativity and modernity," states the foreword to the first major book dedicated to this monolithic designer name. "This pursuit has pushed Prada beyond the physical limitations of boutiques and showrooms, provoked an interaction with different and seemingly distant worlds, and introduced a new way to create a natural, almost fashionless fashion." More than any other globally recognised luxury-goods company, Prada has sought to experiment and innovate, to push at the boundaries of fashion and anything else it touches – from fragrance to yachts – taking any interested party way beyond what might be expected from the comparatively straightforward appeal of designer clothes and accessories, however arresting these may be.

Both in terms of business models and sheer creativity – and anyone who knows anything about such things understands that the two go hand-in-hand, as do husband-and- wife team Patrizio Bertelli and Miuccia Prada, Prada CEO and designer respectively – this viewpoint permeates everything. The aesthetic of the clothes, which remain both instantly recognisable and highly unconventional, is, of course, driven by it. Then there's the patronage of contemporary fine art: the support of the Prada Foundation for Anish Kapoor, Louise Bourgeois, Dan Flavin, Gary Hume and more; the commissioning of landscape-transforming architecture, most remarkably in collaboration with Rem Koolhaas; and the more recent embracing of fashion film and new media.

All of this is gathered together in this brilliantly edited and remarkably complete new tome that takes the Prada devotee behind the scenes in the ateliers, where fine leather is worked into covetable shoes and bags; the studios, where the world's most bizarrely beautiful fabric combinations are tried out; and on to the catwalk shows and iconic print campaigns that market them. All of this amply demonstrates Miuccia Prada's overriding sentiment that, "Just to do a few ultra-sophisticated things for the connoisseurs, as they are called – for me, that's completely boring. You want to be understood by the sophisticated few but you also have to be more loud somehow, otherwise your message doesn't go through."

Indeed, Prada is almost alone in being respected by the fashion elite while reaching out to a far broader and determinedly international audience. "I am interested in communicating with the world by selling to many people. It's much more challenging. And so it's about having to deal with opposites: with sophistication because, of course, I like it and it's part of my story, but also with being in contact with the world."

That story began in 1913, when the well-off, as opposed to ostentatiously wealthy, Prada family – and specifically Miuccia's grandfather, Mario – went into business supplying luxury products, from glasswear to luggage. The first Prada store was in the (remarkably conservative, by today's standards) Galleria Vittorio Emanuele II shopping arcade in the heart of the city of Milan, and it catered to everyone from monied Milanese party animals to Italian royalty.

Miuccia was less than anxious to take to the helm of the company which passed down to her parents, even though it was clearly expected of her. Instead, she studied political science at the Statale University and mime at the Piccolo Teatro. "It was an excuse not to talk," she has since said by way of explanation. "I've always been shy." She also, like many others of her generation, had by then become a signed-up member of the Communist Party. "I was young in the 1960s, when Italian society was first becoming obsessed with consumerism, but my big dreams were of justice, equality and moral regeneration. I was a communist, but being left-wing was fashionable. I was no different from thousands of middle-class kids."

By the mid-1970s, she relented, entering the family business to oversee the design of accessories. It wasn't until 1978, however, when Prada met the outspoken entrepreneur Bertelli and they struck up a partnership, that the more fashion-led product, which by the late 1980s characterised the brand, was introduced. "I had to have a lot of courage to do fashion because, in theory, it was the least feminist work possible, and in the late 1970s, that was very complicated for me," Prada has said of her ultimate decision to move into fashion design. "Of course, I liked it but I also wanted to do something more useful." The resolution of these two sides of her character remains central to her formidable creative ' output. "When people think of fashion, they prefer to see the crazy side, the clichéd side, and actually I think that is wrong. Fashion is an important part of a woman's life. It's a question of aesthetics and that is in no way stupid or superficial."

In 1987, Prada married Bertelli or, as the latter has famously put it, "Miuccia was such a first-rate worker and designer. I knew it would be cheaper in the long run to marry her." Today, stories of the couple's temperamental working relationship are legendary. "When they say we scream a lot, it's true," according to Prada herself. It is, of course, part of the couple's creative process, although, by all accounts, unsuspecting onlookers would do well to steer clear.

Screaming aside, in the early 1990s, Prada had its breakthrough in the form of the black nylon bag complete with triangular metal branding. "I wanted to do something that was nearly impossible," Prada argues, revealing a typically ambitious and uncompromisingly pioneering approach. "Obviously it made sense, because now black nylon is everywhere." Equally significant, while Prada's main competitors – Gucci, in particular – were content with producing the same immaculately crafted and eye-wateringly expensive, status-driven accessories season after season, "I treated bags as if they were fashion. This was something practical but also very luxurious. Those bags were more expensive than the leather ones because learning how to work with the nylon took three or four years; we had to develop the technique ourselves."

The proudly utilitarian mindset behind Prada bags and luggage made it the most fashionable brand to see and be seen carrying throughout that decade. Newly reintroduced, the Prada nylon backpack, in particular, remains a bestseller to this day. In terms of fabric development, meanwhile, Prada continues to produce ever-more complex, painstakingly researched prints and materials to the point where, more often than not, the end result – while still rooted in the highest-quality traditional techniques – is so unfamiliar that the hapless fashion critic is left lost for words.

In 1988, Prada womenswear was introduced for the first time, followed by the more light-hearted Miu Miu collection in 1993 (called after its creator's nickname). In 1994, the designer expanded into menswear and, in 1997, the Prada Sport line was born. The centrepiece of the book is a gatefold spread of all the key looks for Prada womenswear (and menswear) since the designer started, and it is nothing if not testimony to the risks she has always been prepared to take.

From the brown nylon wraps of the first collection (although the Prada rucksack is black, Miuccia Prada prefers browns because "it's just the least commercial colour"), to determinedly dowdy skirts and jackets printed to mimic the tabletops of 1950s American diners (spring/summer 1996), and from the hugely influential beige cardigan and lipstick print knee-length skirt of the "sincere chic" collection (spring/ summer 2000) to the, in her words, "fattening" tufted alpaca skirts of autumn/winter 2008 and this season's tailored wool micro-shorts worn with nothing more haute than waders, Prada's pioneering creativity is on every piece. As the world of designer fashion has gathered speed to the point where even the most dedicated follower struggles to keep up, Prada has picked up momentum. Prada collections and the selling of them – via show spaces complete with elaborate backdrops, online and print advertising and more – change direction at a pace that decrees that both the high street and, significantly, others' catwalks are following their lead years after.

"In fashion, once you've got something, you're already thinking about what's next," Prada says of her restless spirit. "Maybe it's a little hysterical. Now, every day I'm thinking about change. It's a constant anxiety that is probably a reflection of society's anxiety in general. The big deal about fashion is really very recent, this frantic pursuit of newness. It may be a good thing, or a bad thing, but it's really defining this moment."

More timeless is the view that, "What you're wearing is what you're thinking. It shouldn't be something external but a part of you. I think that men, as well as women, want to embellish themselves, to be more creative. But that's not easy to do in a new way. What I've been working on for some time now is a search for beauty. How is it possible to be decorative? And what does it mean, beauty for men and women today?"

'Prada', the book, is available at Prada stores worldwide, at www.prada.com and at selected bookshops