YouTube’s Susan Wojcicki: 'Where's the line of free speech – are you removing voices that should be heard?'

As the crisis-hit video site struggles to stem the flow of extreme content, the CEO talks about her role as the internet's gatekeeper

In YouTube's fashionable central London "space", where good-looking young people mill around and help themselves to the well-stocked free kitchen, there is a noticeboard that asks staff and visitors: What could we do better? On one of the sticky notes, someone has written "Nothing!!" It would be reassuring for the executives who run the video site if that were true, although not many would agree that it is. Susan Wojcicki, YouTube's CEO, who is in town for a three-week tour of Europe, is one of the most impressive and powerful women in tech - and also one of the most beleaguered.

We meet in one of the studios, where YouTubers with more than 10,000 subscribers can make videos, and sit on sofas in a set with a faux brick-wall backdrop, which gives a slightly unnerving sense of fake cosiness. Wojcicki (pronounced "Wo-jisky") seems friendly but businesslike; chatty, but is careful about what she says. There is a lot to talk about: sexism in tech, the power of social media, being a working parent of five - and especially the crises that have engulfed the company she runs, particularly this year.