What I'm Wearing: The perfect wedding guest outfit

Skirt suits can look gorgeous, but might not take you through to evening. Consider day cocktail wear - a crossbreed I didn't believe actually existed until I saw this dress...

BY Lisa Armstrong | 21 July 2012

Dress, £950, Suzannah; suzannah.com. Earrings, £135, and bracelet, £200, both CH Carolina Herrera; 020 3441 0965. Rings, Lisa’s own. Shoes, £55, Topshop; topshop.com Photo: Zac Frackelton

Thinking ahead, and being organised, September is the perfect time to go to a wedding, isn't it? If we're being hypercritical, florally speaking, it isn't entirely ideal, what with roses, bluebells, tulips, peonies, camellias and just about every other bridal favourite being six times the price they were in June. But that's the bride's problem. We just have to show up. And 99.9 per cent of the time it's warmer than June (or July, or August).

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From a guest's point of view, September's got it all. You've still got the holiday tan. If you've been mathematically precise about the timings on your hair-washing schedule, you may even have a bit of beach hair going on. (Isn't it amazing, by the way, that however many hundreds of pounds you lavish in the salon, your hair always looks best on day 11 of the holiday, when the ratio of sand to salt, sweat, sun streaks and the leftover SPF24 oil conditioner that you sprayed in on day one, but forget to reapply thereafter, has reached its optimum balance?). And as usual, there's never any one around who will really appreciate the full glory of your fabulously, effortlessly, chicly tousled hair, husbands and children obviously being oblivious to whatever you do with it. Well, save it all up for the September wedding round and there will be.

If the wedding takes place in earlyish September, you may even have retained some vestigial traces of that relaxed, staying-up-till-2am, siesta-after-lunch glow, although obviously not if you've had to go through border control at any of our magnificent flagship airports. In which case, I recommend François Nars's blusher in Orgasm. Does what it says on the tin.

READ: What I'm Wearing: Lace

Anatomically, then, your body is at its wedding-guest peak. All you need is an outfit. I must confess that this year I've found it a struggle to find dressy clothes that I've really fallen in love with. There have been plenty of dresses, but the exploding prints make many of them a bit of a one-wear wonder. Don't get me wrong, the right print is a joy forever, but maintaining the integrity of a pattern, especially if it's a landscape or a portrait, can be a headache if you need to get the dress taken in or out. And they can date. Horribly.

Skirt suits, matching or mismatching, can look gorgeous, but might not take you through to an evening party. A different option is "day cocktail wear" - a crossbreed I didn't believe actually existed until I saw this dress. It's plain and demure, but with plenty going on, from that lovely full silhouette to the sheen. And it's all perfectly under control.

The skirt, for instance, isn't a huge pom-pom. There are no underlayers of tulle - never a good look on older women. It's a heavy-duty duchesse satin that holds shape without feeling remotely stiff and has a lovely gleam without looking tacky. Round necklines suit just about everyone, and as for the sleeves - how often do you find short sleeves the right length? Admittedly, the colour isn't any more retiring than the most virulent print, but parties are not the moment to come over all introverted and it's easy to ring the changes with belts, jewellery and contrasting accessories. Chartreuse is amazing for formal wear, not just because it works so well with black, navy, gold, orange and brown, but because it guarantees that even the sweetest, primmest style won't look twee. This dress is by Suzannah, who's become a bit of a favourite with the royal set. Obviously it costs a bomb, but it's a classic.

Equally obviously, one should always be suspicious of single-name-only designers. But on the evidence of this dress, and other, more affordable ones on her website, including lovely Forties-inspired tea dresses from £375 (there's a bespoke service too), the case against Suzannah is dismissed.

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