Smell of success: Kilian Hennessy evaluating his perfumes in his laboratory / Laura Moss


"It was brave and it was a risk. But for me there was no alternative. Because without risk there cannot be the joy of bringing something new to the market." So says Kilian Hennessy, in typically grand, Gallic style. He is speaking of his collection of independently owned fragrances – By Kilian – that is five years old and also, incidentally, typically grand and quintessentially Gallic by nature. It's safe, if presumptuous, to assume that Hennessy – who is the heir to a long line of Cognac makers and the grandson of the co-founder of LVMH (Moët Hennessy Louis Vuitton), the world's largest luxury goods conglomerate – never needed to work.

But that wouldn't have suited the restless Frenchman. And so work he did, training alongside some of the great perfumers, creating and marketing scents, initially at Christian Dior (LVMH), then Paco Rabanne (Puig), Alexander McQueen (YSL Beauté/The Gucci Group) and, most recently, Giorgio Armani (L'Oréal). He's nothing if not outspoken. "If I was interested in making copies of things that already exist, I would have stayed with the big brands," he says. And he should know: he worked for them for 12 years.

Meet any perfumer who is passionate about his metier and it won't be long before the thorny subject of the IFRA (International Fragrance Association) raises its head. To many, this is, ironically, the most significant obstacle where the production of contemporary fine fragrance is concerned. It is the job of the IFRA "to ensure the safety of fragrance materials through a dedicated science programme", according to its own website. "This focus on fragrance safety helps both the consumer and the environment." Whether it helps the creators or indeed the venerable names for which they create is less clear. "They've messed up all the great scents," says Hennessy matter-of-factly. He has already been forced to "re-touch" two of his own fragrances due to the IFRA's changing standards. "IFRA keeps sending out new recommendations and we have no choice but to follow their guidelines. They're killing perfume and it's just about allergies and they're becoming stricter and stricter."

It wasn't always this way. "Like, your grandmother lived with perfume very easily and if, one day, a woman had an allergic reaction, she could just stop wearing it. It wasn't the end of the world. Or she could put it, perhaps, on a sweater, on her jacket, not on her skin. This industry is just so scared." There are certain ingredients integral to the history and stature of perfume that, in today's cautious climate, and not unlike unpasteurised cheese, are simply a no-no.

The pressure on perfumers to perform under ever more demanding circumstances is, to more than a few insiders, equally responsible for the play-safe tactics behind many modern, branded scents. These are famously the entry point to the world's most revered fashion names, but not always now the inspirational olfactory experiences they once were. "Today, the big brands are in exactly the same position as the film industry," Hennessy says. "They have to do blockbusters and they have a month of sales to prove themselves. After one month, the perfume will be judged a success or a failure. If it's a failure, all investments will be cut immediately."

This, he argues not unreasonably, means that perfumes such as Angel and Fahrenheit, created by Thierry Mugler and Dior respectively, and widely recognised as two of the most ground-breaking, money-spinning fragrances of the latter part of the 20th century, would never have happened. "It took three years for both of them to be accepted by the consumer because they were so new. Things like that cannot exist any more."

The exception that proves the rule is the fragrance devision at Chanel, he says, where master perfumer, Jacques Polge, who has worked his magic there since the 1970s, is allowed unprecedented freedom and creative control. Interesting, too is Louis Vuitton's soon-to-launch foray into fragrance. Jacques Cavallier-Belletrud, recently employed as perfumer by that brand, is among Hennessy's mentors a veritable god in fragrance circles. Ask Hennessy what the most important scents in history are, meanwhile, and he cites No 5 (of course), Opium, Poison, Fahrenheit, Issey Miyake, Jean Paul Gaultier ("the first one"), Aramis, Escape... "For me the 1970s, Eighties, and Nineties were the 30 most glorious years in perfumery."

For his part, he had never intended to set up his own business. But, at L'Oréal, where he and the perfumers he worked with were expected to produce as many as four new fragrances each year, he was finally given the push that he needed.

"I kept resigning and going to other groups," he says. "I was raised by the former president of Dior, Maurice Roger. He did Poison, Dune, Fahrenheit, Dolce Vita, all these creations and that culture was no longer there."

So, Hennessy jumped, rushing in where angels fear to tread, which is immediately apparent upon contact with pretty much all of the scents that bear his name. He says that he thought long and hard about using that, too. "I knew if I put my name on it I would never sell it," he says. "So it was a question of whether I wanted to pass it on to my children one day."

It may not be possible to love all the By Kilian fragrances – at least some are plain confrontational – but a reaction will be provoked one way or another. As is so often the case, despite any amount of market research that might suggest otherwise, his refusal to compromise has proved fortuitous. Hennessy says that among his bestselling scents is Straight to Heaven. It's a far-from-predictable rum-patchouli accord and "for me, its popularity was a huge surprise. There's nothing easy about the scent. It's rough. It's raw. There's no freshness. It's really unique. Once I was walking in the street and a man passed by and said to me: 'Straight to Heaven'." He tells another story of a male friend wearing the same fragrance in New York when a perfect stranger – female – came up from behind and licked his neck.

Kilian Hennessy, now aged 40, graduated from the Sorbonne in Paris, where he studied language and communication and wrote his thesis on the semantics of smell before working for the aforementioned companies. "For the first five years I worked until 2am or 3am every single night," he says. "In music you have seven notes, and imagine already what you can compose. In perfumery you have 3,000 notes to learn and then all the accords." Learn them he did but, unsurprisingly given his academic background, for him, all great perfumes – and certainly any of his own – begin with a narrative. "It's like with No 5. Really, the story started with a journalist saying to Marilyn Monroe: 'Who are you sleeping with now?' She answers: 'Naked with Chanel No 5.' And there it is. You have seduction, you have sensuality, you have an icon. You have everything."

In the first instance, Hennessy created the L'Oeuvre Noire series, working predominantly with Calice Becker, responsible in her time for the creation of both Dior's J'adore and Marc Jacobs' Lola, and less frequently with Sidonie Lancesseur, a lesser-known nose. Beyond Love, "an incandescent tuberose with narcotic charms" was among the first of his perfumes to be born, not least because both his mother and grandmother favoured the heady white flower. That is among his earliest memories of scent, along with his grandfather's penchant for Dior's Eau Sauvage. In the same series is Love, inspired by marshmallow. (Becker was making them following an old family recipe for her children at home – et voilà!) Others in the collection are based on everything from absinthe verte to iris and from honey and tobacco to oud.

From the names to the packaging, Hennessy aims to express both complexity and luxury. His perfumes come in carved, black, wooden boxes each of which is opened with its very own key. Bottles rest upon plump beds of satin, like precious jewels. From the raw materials that go into them to the evocative names and the final presentation, they exude a degree of quality that is rare.

Hennessy wears "a wardrobe of scent" – predominantly his own. "I wear A Taste of Heaven most, it's a very dandified scent, a lavender with a dry down of vanilla," which reminds him of Obsession, a long-time favourite. "At night I wear Back to Black Aphrodisiac – honey, incense, tobacco – very long lasting. When I wake up in the morning, it's still there. On weekends, when I'm in jeans and a T-shirt, I wear either Prelude to Love, Sweet Redemption or [the recently launched] By Harmony."

Put crudely, By Kilian is not cheap. He says: "I don't think it's a lot of money. The luxury brands have been saying to customers for the past 80 years that a luxury fragrance costs £50. So generation after generation it has been established. When someone comes along with a perfume that costs £145, they're like, 'It's very expensive'. But it's a question of what you are giving the customer for that £145? There are now a few brands that have come up with a higher level of perfume and hopefully things will change." He says that Creed, the British, family-owned perfumer since 1760, is a business model that he aspires to. And Hennessy recently read a profile of Steve Jobs. "There is not a single product designed by Apple that costs less than a few hundred dollars; at one point Steve Jobs said it is not that Apple has become mass market, it's that the market has now reached Apple's level. Hopefully that will happen with fragrance. Hopefully more and more people will say, you know what? £145 for that product is not a lot of money."

By Kilian, available exclusively at Harvey Nichols,