Window dressing at London's Dover Street Market

In fashion, the balance between art and commerce is precarious at the best of times, but one designer whose revolutionary retail strategy has only served to reinforce her position as a true visionary is Rei Kawakubo. The Comme des Garçons designer's multi-brand London emporium Dover Street Market remains a byword for what is exciting, interesting and covetable in the industry.

Sprawling over six floors, the store is housed in a Georgian building in Mayfair, on a road on which art galleries and offices jostle alongside an increasing number of boutiques such as McQ, Acne and APC. A perfectly orchestrated version of this mish-mash is part of the store's appeal – elegant designs sit next to avant garde, designers featured range from the established to emerging. Every season a biannual process called tachiagari sees the store close for several days, during which time brands rejuvenate their own spaces to house new-season merchandise, film and theatre designers create work for the shared spaces, and artworks are installed.

This eclectic, art-led, approach ensures that the store is constantly evolving: “I want to create a kind of market where various creators from various fields gather together and encounter each other in an ongoing atmosphere of beautiful chaos; the mixing up and coming together of different kindred souls who all share a strong personal vision,” Kawakubo says of her ground-breaking approach.

Indeed, in contrast to most fashion stores, the windows of Dover Street Market serve as a gallery space for site-specific installations created by designers and artists who are given absolute freedom with the space. This Friday, the latest installation, by young London-based designer Phoebe English, will be revealed.

English is understandably excited about this invitation when I meet her at her east London studio, where she is working on a large-scale construction inspired by an apron-skirted dress from her spring/summer 13 collection. “It's really exciting to work in a different medium, a different space and without a body being there,” says English, who won the L'Oréal Professional Creative Award for her MA collection on graduating from Central Saint Martins in 2011.

“Dover Street Market was our first stockist. When I graduated after winning the L'Oréal prize I felt a bit swept along by all the attention. The plan was to go away and make some new work, to be as quiet and invisible as possible. I didn't have any grand plans for that collection, then Dover Street Market picked it up which was just incredible. It meant a lot to Rose [Easton, English's business partner] and me – it gave us the confidence to launch the label and register our company. Really Dover Street Market was the beginning of everything.”

“[Phoebe] offered a new and interesting perspective,” says Dickon Bowden, vice-president of Dover Street Market, of the decision to buy her work. “It is always important to be bringing new creations, new opinions and new perspectives to everything we do. We have always sought to nurture and present new and emerging designers.”

For English, this is certainly a big deal – she admits that feeling at home in the store is a dream come true, and one that she had never contemplated as a shy student: “At Central Saint Martins, in the first year, you have a project where you go and visit all the shops in London. I remember going to Dover Street Market and being so intimidated by this amazing establishment. I don't think I could get further than the doormat.” English looks back with humour: “I felt so dishonest going in there just to look around and not being a customer. It's so funny, I go in there now and it's such a different experience.”

For her window display English, whose studies focused on knitwear and textiles, has created a large orb of blue glass beads that will be suspended from the ceiling by a single wire. “I wanted something that looked as though it was floating or hovering – a lunar orb. The textiles we're using are all glass and we found that during the [spring/summer 13] show you got a really great reflection of the show lights while the girls were in motion. We're hoping that the light will sort of sparkle across the surface.”

There is something ephemeral about English – a sense of fragility emanates from her wide eyes, softly spoken voice and messily pinned platinum hair. Indeed, it seems that if it were not for the intervention of her business partner, her brand might never have got off its feet, let alone become such a rapidly growing success story. “Rose is just incredible, there's no way I would be able to do this without her,” English says of her confident colleague.

“She was my first ever customer – she ordered a dress from my MA collection for her birthday. I had to move everything out of Central Saint Martin's after six years of studying there, so I piled my studio into my little bedroom and was working out of that. I got this email – I'm not very good with correspondence so I didn't reply, and she sent another, and after a week I replied: 'I really don't know if you want one of these dresses, it's not going to be comfortable to wear.' She replied saying 'Yes, of course I want it.' We were doing her fitting and she surveyed this scene of disarray and said 'I think you need some help here.' A week later we went for a drink and that's how it all happened. She's my friend, my business partner and my creative collaborator. I can be steely but that's not natural – we have very different personalities which complement each other really well.”

“Phoebe's personality is so incredibly different to my own,” Easton agrees. “Making that dual partnership work is interesting. We always balance each other out and push each other. There are a lot of people who are creating dresses that are very formulaic – zip it up and you're in that outfit and become a version of that design, and that designer. All the clothes that Phoebe makes are very much influenced by the wearer – you interpret them, you wear them and they become a part of you.

“That's really important to us – how women can interpret it themselves – that's a really exciting thing to watch develop.”