'IT' Bags.

This season it's Celine. Last year it was Balenciaga. And who can forget the popularity of the 'Stam' bag from Marc Jacobs circa 2007? Every season there's a new 'it' bag on the scene that celebrities can't get enough of. Of course there are a few which stand the test of time including the Chanel '2.55', the Hermes 'Birkin' and the Louis Vuitton 'Speedy', but what makes certain bags so enticing to women for limited periods of time? It can't be the price tags! A Birkin can set you back upwards of £10K. (And I don't even want to mention the waiting list! 5years+ if you want to pay the RRP)

In my opinion, it's PR and marketing strategies such as celebrity endorsement, that ensure the highest amount of sales, and ultiamtely profit, for these designer brands. Think about it, women interested in fashion are obsessed with Alexander Wang bags as his designs are modern, edgy and perceived as cool. Team this brand identity with an equally cool celeb, cue Rosie Huntington-Whiteley, and you've got a hit.

Rosie Huntington-Whiteley with her 'Rocco' Alexander Wang bag.

As I said at the start, the current favourite go to bag amongst celebrities is from Celine. The aptly named 'Luggage' design comes in an array of colours, sizes and fabrics. Everyone from Leighton Meester to Nicole Richie to Kourtney Kardashian have been snapped with the bag. I think the key with a bag that can transcend through any age category is to keep it appropriate for you. I love how Miley Cryrus has kept it young with a neon yellow version of the bag and Oprah Winfrey has kept it low key in nude.

A selection of celebs carrying their 'Luggage' aroud, proudly.

It's only a matter of time before another designer brings out a new 'it' bag. My advice to them: be generous! Give freebies to celebs of all ages. That way, you're not alienating any possible customers. To stop the younger audience feeling the bag is dowdy or too old for them, follow Celine and use interesting fabrics or eye popping colours to keep the bag young and 'cool'.