The 'Clown' singer, Olympic champion and model lead the 2014 charity call-to-arms, asking the fashion-forward to 'Wear Your Support' thanks to specially-designed collections from a host of high street retailers.
At least 30 per cent of proceeds from the sales go towards funding Breakthrough Breast Cancer's work. The organisation, which brought the campaign over to the UK in 1996, has so far raised over £13 million towards beating the disease.
Emeli revealed the campaign was extra special for her because she wants to honour the memory of her friend Narcisse, who passed away from breast cancer.
She said: ''I'm taking part in this year's campaign in memory of my friend Narcisse; wear your support and help make a difference in the fight against this terrible disease.''
London 2012 heptathlon gold medal winner Jessica commented: ''Fashion Targets Breast Cancer supports really important research that will save lives. I'm proud to be doing my bit in helping encourage all of you to wear your support and help stop this devastating disease.''
Fashion Targets Breast Cancer has partnered with M&S, River Island, Warehouse, Topshop, Laura Ashley, Debenhams and Superga to create everything from sundresses to swimwear, priced from £2 to £85, especially for the campaign.
Fashion Targets Breast Cancer was set up in 1994 by Ralph Lauren after he lost his close friend to the disease.
For more information on how to get involved visit fashiontargetsbreastcancer.org.uk, follow @fashiontargets or check out the range via the #wearyoursupport.
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