WATCH:Episode Four Of Alexa's Future Of Fashion

WHAT does a buyer actually do?How does trend forecasting work?How did Paul Smith become Paul Smith and why is he talking about bosoms and underpants?All these questions are answered in the fourth instalment of Alexa Chung's acclaimed documentary series for British Vogue.

With the rise of digital and the sheer volume of ways in which to attract attention and absorb information, the number of roles that exist in the fashion industry today are more varied and radical than ever.Smith kicks off Chung's investigations by discussing how he has grown his eponymous label and kept it relevant and commercially successful without compromising his traditional cutting techniques.

Judd Crane, director of womenswear and accessories at Selfridges, describes the various routes into becoming a buyer, and the importance of understanding the customer as well as appreciating the behavioural elements of fashion.We are also introduced to Lauretta Roberts, director of brand for WGSN, who talks Chung through how the world of trend-forecasting has come about and shows her round the offices of the fashion analysis powerhouse.By the episode's end, our intrepid reporter is enquiring about a job for herself there.

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