Strictly Come Dancing (informally known as Strictly) is a British dance contest show in which 15 celebrities partner with professional dancers to compete in mainly ballroom and Latin dance. Each couple is scored by a panel of usually 4 judges. The title of the show is a continuation of the long-running series Come Dancing. The format has been exported to 60 other countries—under the title Dancing with the Stars—licensed by BBC Worldwide, and led to a modern dance-themed spin-off Strictly Dance Fever. The Guinness World Records named Strictly to be the world's most successful reality television format in 2010. The series is currently presented by Tess Daly and Claudia Winkleman. Bruce Forsyth co-presented the series with Daly until 2014. The series has been broadcast on BBC One since 15 May 2004, typically on Saturday evenings with a following Sunday night results show. From series 2 onwards, the show has been broadcast in the run up to Christmas. With its high viewing figures, Strictly Come Dancing has become a significant programme on British television. Eighteen stand-alone Christmas specials and nineteen charity specials have also been produced. Producer Richard Hopkins, who had produced the first UK series of Big Brother, unsuccessfully pitched the idea of a modern Come Dancing to the BBC under the title of Pro-Celebrity Dancing in 2003. Later, entertainment executive Fenia Vardanis also suggested reviving Come Dancing, so Jane Lush, the then head of BBC Entertainment, put Hopkins and Vardanis together to develop the show. Hopkins then called in Karen Smith, who had just produced Comic Relief Does Fame Academy for BBC One and The Games for Channel 4, to help lead the development of the show and launch the series. Smith was the show-running Executive Producer of the first three series, and of sister show It Takes Two. She then took the role of Creative Director of BBC Entertainment whilst still overseeing series 4 and 5. Hopkins later took the format to America himself when the BBC dismissed the idea of selling it abroad, as they felt it was too British.