Try out a trench coat - you'll never regret it

Here on the Standard fashion desk, we've lost count of the number of times we've left the house in our winter coats only to find ourselves melting by the time we've reached the Tube station. And that's before we've even got into the train. Life is tough, innit?

However, the solution to these thermostatically random, shower-speckled days is simple: a trench coat.

Gallery: Trench coats that make a fashion statement

This classic garment goes in and out of fashion but while it isn't always "in", it's never, ever "out". Because of this, it is a genuine investment buy. You will never regret buying a trench coat.

The trench coat is most definitely "in" this autumn. At the Paris shows last month (Paris was also suffering from a broken thermostat, and frequently felt like Ibiza in June), trench coats were out in force among the fash pack, usually serving as an accompaniment to this season's pencil skirts.

But while a trench coat looks marvellously sharp with a pencil skirt, 15 denier tights and simple black stilettos (very "job interview"), one of its best features is its versatility.

It works just as well for work as for a Saturday afternoon walk, worn open so that it billows, with mid-blue jeans and white sneakers.

The trench was not invented: rather, it evolved over the years as a utilitarian garment whose every feature - weatherproof fabric, gun flap, epaulettes - can be linked with a function: little surprise, then, that it is so versatile.

Length is a hotly contested issue. Burberry's new "mini trench", which falls to mid-thigh, is perfect for mini-skirts, of course, but you have to have the legs to carry it off, and it can look a little as though you forgot to put your bottom half on.

Conversely, a coat that runs to mid-calf can look wonderful on taller women but a little frumpy on smaller ones, especially when worn without trousers being visible underneath.

For a trench coat that will withstand the vagaries of time, you should probably stick with one that falls to just below the knee: belted, it will ride up a couple of inches anyway, making it the perfect length for trousers or skirt.

On the subject of belts: we're not quite sure why, but the fash pack never, ever wears their trench coats belted, but tied in a double knot (see Gwyneth Paltrow/Carla Bruni Sarkozy for style tips).

Whether this makes them quicker to unfasten and slip off is debatable, and depends very much on how tightly you tie the knot in the first place.

Perhaps the primly belted trench looks a little Inspector Clouseau for modern tastes, while a knot looks more bohemian.

Burberry and Aquascutum might have the longest and most stately heritages - both were founded in the 1850s - but they are far from alone, these days, in producing trench coats.

For a designer take, Jean Gaul Gaultier and Vivienne Westwood's are both beautiful, while on the high street, Gap, Top Shop and Zara have some of the best and most reasonably priced of the season, each under £100.

Gallery: Trench coats that make a fashion statement