Joanna Shields has left her position as Vice-President and managing director for Europe at Facebook to become the new CEO of Tech City.

Shields will start her role in 2013, with the aim of leading the group of firms based in London's East End into becoming the European equivalent of California's Silicon Valley.

Prime Minister David Cameron praised the appointment of Shields, saying that he felt, "Joanna's experience will be hugely valuable in supporting Tech City as it goes from strength to strength".

The 50 year old American born businesswoman has previously worked at AOL, Bebo and Google, and was voted in 2011 the most influential person in European technology by Wired magazine.

Shields replaces previous CEO Eric van der Kleij, who stood down from the position earlier this summer.

Written and Presented by Alfred Joyner