LONDON, ENGLAND - JUNE 01: Singer John Legend performs on stage at the 'Chime For Change: The Sound Of Change Live' Concert at Twickenham Stadium on June 1, 2013 in London, England. Chime For Change is a global campaign for girls' and women's empowerment founded by Gucci with a founding committee comprised of Gucci Creative Director Frida Giannini, Salma Hayek Pinault and Beyonce Knowles-Carter. (Photo by Ian Gavan/Getty Images for Gucci)

LONDON, ENGLAND - JUNE 01:  Singer John Legend performs on stage at the 'Chime For Change: The Sound Of Change Live' Concert at Twickenham Stadium on June 1, 2013 in London, England. Chime For Change is a global campaign for girls' and women's empowerment founded by Gucci with a founding committee comprised of Gucci Creative Director Frida Giannini, Salma Hayek Pinault and Beyonce Knowles-Carter.  (Photo by Ian Gavan/Getty Images for Gucci)