To Berluti, who likens the business to a convent, shoemaking is a quasi-monastic ritual that must be undertaken with the utmost reverence. To label her a mere bootmaker wouldn't do justice to her craft; she is part sculptress, part physiologist, part artist and part mind-reader. She can sense what kind of shoe a man will require just by looking at him.

'The way he moves, sits down, pushes a door open, leads me to understand very quickly whether he wants a shoe that will be seen straight away or a shoe that people will discover bit by bit.'

So where does this intuition come from? 'Everything I've learned is because I wasn't allowed to do what a normal bootmaker would do, so I had to learn other ways,' she says. Berluti's delicate features and bird-like frame belie the fact that, as one of a tiny number of women to succeed in the men's shoe business, she has a will of iron. Her education in the ways of men's feet began when she was discouraged from assisting in the Berluti workshop on rue Marbeuf, near the Champs-Elysees in Paris.

'Nobody wanted a woman in there,' she says. 'It was a very difficult time and I found it impossible to express myself.'

What would become a flood of expression began with a mere trickle. To begin with, she was allowed only to dust the shoes. But in the back rooms of the workshop she secretly began dabbling with oils and cloths and experimenting with colours and textures, laying the foundations of Berluti's unique colour treatments. Her workshop is the ultimate expression of her creativity with colour, a rainbow riot of hues, making for a hallucinogenic experience as you enter from a cobbled, ivy-covered courtyard through a medieval door. 'The only way I could give [the shoes] my own stamp was through the work I was doing with the colour pigments, you see.

'It was always about finding other ways to understand the foot,' says Berluti. 'What I wanted was the happiness of the foot and eye. The look is the about the colour and the happiness is the comfort.' In her early twenties she set about researching the physiology of feet, from which she learned that men 'disregard and treat them badly'.

To counteract this, Berluti has perfected a creative process whereby a made-to-measure pair of shoes takes a minimum of nine months to create. At the client first's meeting with Berluti, she determines the kind of shoe he requires. A wooden cast is made of his feet. Damp leather is then manipulated around the cast and allowed to dry.

'It must be given time to breathe,' says Berluti, who treats her materials with the care of a surgeon. 'Leather is a living material. You must be very delicate with it and not brutalise it.'

She admits that in the world of fast fashion and seasonal trends, hers is an antiquated kind of craftsmanship. 'Berluti isn't about autumn/winter, having to do a collection. We don't create because we need to, we do it because clients make requests. It's a very artistic approach,' she explains.

Before I leave, Berluti shows me her collection of wooden casts of famous clients' feet. She has decorated each one to reflect its owner. 'Andy Warhol,' she says, pointing to a cast covered in Coca-Cola logos. 'Frank Sinatra,' - she gestures towards one covered in piano keys. A pearl, feather and richly embroidered pair are Visconti's. '[Jean-Paul] Guerlain,' she says, pointing to another, mysteriously covered in keys.

Why the keys? 'Ah, Monsieur Guerlain always told me that he had the key to the nose.' An appropriate homage from the woman with the key to the foot.