Six days ago the future of Britain’s fashion designers looked bleak. New York Fashion Week had decided – as is often the way when America says positive things about the Special Relationship – to change the dates of its fashion week from next February, effectively squeezing London Fashion Week out of the international calendar.

Things in the financial world didn’t look too clever either, and that’s never good news if you make expensive clothes and accessories.

While worlds were turning upside down on Wall Street and in the City, London Fashion Week underwent its own internal revolution. Most shows started only 30 minutes late, practically premature by ye olde standards.

Models seemed, for the most part, healthy, some even looked familiar. But it was when a pair of bare breasts bounced down the catwalk at Vivienne Westwood, and I found myself thinking ‘how quaintly old-fashioned’, that I realised London really had changed.

It was the clothes themselves, though, that surprised most of all. There was slick (Osman Yousefzada’s slinky, yet flattering tailoring), inventive (Christopher Kane’s laser cut organza dresses), beautiful (Erden’s gorgeous florals), commercial, without being dull (Aquascutum, Nicole Farhi, Amanda Wakely, Jaeger) and all of them were tremendously colourful.

Quite apart from all that tailoring, you’d be forgiven for thinking, crisis, what economic crisis? Especially once the parties kicked off. London Fashion Week has always burnt the candle at both ends, with five or six East End raves a night after the shows finish. But last week saw something more evolved: the grown-up party, with tables, food, fancy venues and everything. That can only mean one thing – the big brands have moved in, and so it proved. Lanvin, Diane von Furstenberg, Dunhill and the Labour Party all saw a chance to capitalise on London’s design energy. Sarah Brown’s cocktail party for the fashion industry at No 10 revealed two interesting nuggets.

First, that a considerably slimmed-down Mrs Brown had written to the organisers of New York Fashion Week, asking them to think again. These are not affairs in which political figures normally deign to involve themselves, so perhaps figures from the British Fashion Council revealing that the textile and fashion industry is worth £40 billion had an impact after all.

Mrs Brown was wearing Jaeger, by the way, and looked very smart. Apparently she was “freaked out” by the Carla Bruni Sarkozy experience. Well, who wouldn’t be?

The second revelation of the evening was that No 10 requires an urgent makeover. The colour of the municipal park lavatory paintwork in the Cabinet Room is shocking.

If the image of these smart soirées (Princesses Beatrice and Eugenie with Charlotte Casiraghi at Issa, the socialites’ pet dress label) conjures up the Great Gatsby or the Titanic, it’s not because designers exist in a vacuum of chiffon puffs. A new generation is only too aware of the realities of business and consequently many of them look to emerging markets.

They also know that London’s old traditions – half-thought-through ideas and clothes that look as though they’ve been put together with a knife and fork – are an anachronism in today’s market.

Who knows how they stump up for Christian Louboutin shoes for 20 models and engineer such well-constructed clothes when some of them struggle to pay their rent? But it’s probably something to do with pluck and sheer bloodymindedness.

At Vogue’s dinner for British designers, the Editor Alexandra Schulman recalled a similar mood 16 years ago, when London Fashion Week was down to 16 shows and no official venue. A year later, in 1993, Philip Treacy, Alexander McQueen and Stella McCartney burst on to the scene. My, we Brits love a crisis.

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