Behind the lens: How fashion's glossiest images come to life

Many people read fashion magazines for the editorial shoots, but the industry itself is more interested in the adverts, and none are more popular than campaigns which appear in the September and March issues.

Just twice per year, in these months, major brands stake hundreds of thousands of pounds on creating and placing just a few advertising images. The finest – and most expensive – photographers, art directors, models, hair and make-up artists and set designers are all hired to distil the company's current design "vision" down into a commercial message that will seduce customers, while also asserting the brand's cutting-edge aesthetics.

The "collections issues" are where the next season's campaigns are launched. And, as ever, the questions are: who shot what?; who won the prize for "best photographer"?; and which models got the starring roles?

Apart from the collection itself, the advert is the biggest risk a designer takes all season, and the images are an acute barometer of the socio-economic climate in which they are produced.

Click on the links to see the ad campaigns and read Penny Martin's verdict.

1. YSL

2. CHANEL

3. LOUIS VUITTON

4. BURBERRY

5. CHRISTIAN DIOR

6. BALENCIAGA

7. PRADA

8. GUCCI

9. DOLCE & GABBANA

10. MARC JACOBS

11. STELLA McCARTNEY

12. MIU MIU

Penny Martin, is the professor of fashion imagery at the London College of Fashion