As one who has frozen at summer events from Glyndebourne to Ascot, I’ve been trying to find the answer for years. But this year there is a spectacularly glamorous and comforting solution — a divine evening coat. They’re everywhere. Almost every designer from Marni and Paul Smith to Betty Jackson and Cacharel has a version. The great thing about them is that you can wear almost anything you like under them (thermal underwear, John Smedley’s lovely Sea Island long-sleeved T-shirts, black cashmere sweaters, or just a chiffon dress if it suddenly turns hot) and still look beautifully glam. The secret of the coat is that to look suitably swishing and elegant it shouldn’t be in wool (or, put it this way, I haven’t yet seen a wool coat that manages to look right for what are supposed to be languorous summer nights. Wool may provide the warmth but it doesn’t provide the evening glamour). They should be in silk (padded, if you can find them — Issey Miyake does some delicious padded silk coats), brocade or satin. Harrods, Selfridges and Harvey Nichols have a big selection of designers who are worth checking out if you have time.

A glamorous evening coat isn’t going to be cheap but it ought to see you through summer evenings for years to come, so regard it as investment dressing. There’s Miu Miu’s delicious rose-and-cream floral coat (£605 from www.net-a-porter.com ) which is hard to beat for sheer prettiness. Vera Wang has a supremely elegant, structured number in white and mint-green brocade — very, very cool (£1,280 at Browns, South Molton Street, 020-7514 0025), while Jean Muir (Conduit Street, 020-7434 9077) has also turned to brocade for a sophisticated take on the evening coat (£995). The company uses the same brocade to do an equally elegant evening suit (skirt and jacket). Derek Lam (at Harvey Nichols) goes in for a good mix of prettiness and elegance using a lovely red-and-white floral silk, as illustrated here by David Downton.

Finally, for those with more offbeat taste, it could be worth paying a visit to the Hali Carpets, Textiles and Tribal Art Fair this weekend (June 9-19, National Hall, Olympia, London), where there will be any number of fantastic antique coats to choose from. I have a brilliant-blue, antique Korean wedding kimono bought very inexpensively some years ago from Graham & Green; it has been my sartorial lifeline on those evenings when I’ve needed to be glamorous and warm.

At the fair there will be kimonos from Japan and Korea, silk robes from Uzbekistan, Japanese and Chinese silk robes — each will be unique and most of them provide splendidly decorative cover-ups. Karina Duebner of Tamerlane’s Daughters (020-7584 9548 and www.tamerlanesdaughters.com ) offers one-off items of clothing that she calls “a fusion of tribal and couture”. She incorporates antique pieces, embroidery from Uzbekistan and golden amulets from Ottoman wedding dresses, many of which she buys at the Hali Textiles Fair and turns into one-off pieces. She has some good flamboyant evening coats.

Finally, it’s hard to beat the simple elegance of a plain, round-necked, long-sleeved sweater in finest cashmere, teamed with some nice jewellery and a great satin skirt.

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