Shapewear is often seen purely as 'slimming' underwear that people wear when they're desperate to squeeze into a size smaller than normal. And sometimes that is the case - never underestimate the power of a pair of big knickers when your favourite dress is feeling a bit tight! - but shapewear is far more than that.

As well as the tummy flattening and bum-lifting abilities, these foundation garments are also useful for avoiding VPL, creating a smooth line under thin or close-fitting fabrics, or accentuating your favourite body parts.

The right shapewear doesn't need to be tight and uncomfortable. We've come a long way since the girdle. Modern shapewear styles have loads of stretch to provide gentle support, not corset-like restriction, and there's something to suit every outfit.

Here are six ways to improve your look with some cleverly chosen foundations...

You're wearing: a bodycon or very fitted pencil dress (ponti, lycra etc)

Shapewear slip to wear under a bodycon dress

Ensure completely smooth lines under a very tight dress with a full slip like the Assets Red Hot label by Spanx nude sleek slimmers cheetah slip (£62). This is more about smoothing than slimming - don't expect it to flatten a belly completely, though it should help to soften things up! Bodycon or tight dresses often cling to every line underneath, including your bra, so a seamless bodyshaping slip like this will ensure a smoother, bump-free line underneath, covering your bra completely. The hemline is seamfree so it won't dig in giving you a line around the thighs either. The cheetah print panel is just for show - but it makes a change from plain!

You're wearing: a dress with a very fitted waist and a full skirt

Shapewear waist cincher under 50s dress

If you're a fan of the 1950s look, a waist cincher is your must-have shapewear secret. The Miraclesuit full control waist cincher (£34) will give you that waspish waist with a bit more give than a traditional corset (though do invest if you want the authentic look). This hook-and-eye fastened panel sits from below your bra to your hips, gently holding your mid-section in and giving you great posture. Due to the hooks it's not great under very fitted clothes, but works brilliantly under full-skirted, cinch-waist sundresses.

You're wearing: a maxi with sheer skirt or split

Shapewear bodysuit under a sheer maxi dress

If your skirt has sheer panels, layers or splits, you need to give longer-line shapewear a miss. But you can still smooth out the top half with a style like the Trinny and Susannah Magic Body (£55). It's got all the waist, bum and tum shaping capabilities, but the bodysuit style means it works with even the shortest or sheerest of hemlines. It's also designed to be worn with your favourite bra, coming just underneath the band, so if your dress is also low cut, you can wear a bra to suit.

You're wearing: a wrap dress with a low-cut neckline

Shapewear to wear with a wrap dress

If the neckline of your outfit is low, you could opt for one of the styles that sits below your normal bra, but with a fitted jersey bodice like this one, you'd get a much smoother finish and less bulk with a bodysuit with a built-in plunge bra. Gok Wan's sleek bodyshaper from Simply Be (£25) is sold by bra size rather than dress size, promising a great fit, but it also includes useful shapewear touches like the extra panels on the hips, and seaming to cinch in the waist.

You're wearing: flat-fronted or slim trousers / jeans that hug your bottom

Shapewear for smooth lines under fitted trousers

Try some shapewear shorts, like the Trinny and Susannah Shape Up Shortie (£26). They don't have such a high waist as many rival styles, which means they won't stick out above the waistband of your trousers / jeans giving you a 'double waist'. But you still get all the same tummy-flattening, smoothing benefits. The longer hotpant-style shape means that there'll be no visible line across your bottom where your knickers sit either. Just beware if your trousers are super skintight all the way down that you can't see the leg band - you shouldn't if you pick the right size.

You're wearing: a very slinky jumpsuit!

Shapewear to wear with a jumpsuit

If you're wearing a jumpsuit with slim trousers, The classic 3/4 shapewear pants are best for this look, providing you with tummy flattening and shaping all the way through the mid-section and right down the thighs - perfect if you're wearing jumpsuit like this that will cling to underwear in all the wrong places! Obviously this style is also great under dresses if you don't like the restrictive feeling of a slip - there's a reason this shape is always a shapewear bestseller! For cost effectiveness, choose nude which will work under both light and dark colours.

(clothes in pics: trousers from La Redoute, Blue bodycon dress by Diva at Lovarni, strapless floral dress from Style Icons Closet, Sequin waistband maxi dress from Missguided, bandeau jumpsuit from ASOS, Wrap front dress from ASOS curve)