The cover is shot by Mario Testino with styling by Jessica Diehl. (source)
Click here to view last year cover featuring Taylor Swift, here to view 2014 cover featuring Natalia Vodianova, here to view 2013 cover featuring Princess Diana, here to view 2012 covers featuring Jessica Chastain and Kate Middleton, here to view 2011 cover featuring Jennifer Lopez, here for 2010 cover with Lady Gaga and here for 2009 covers with Michael Jackson and Farah Fawcett.