Margrethe Vestager wants to keep European markets competitive -- which is why, on behalf of the EU, she's fined Google $2.8 billion for breaching antitrust rules, asked Apple for $15.3 billion in back taxes and investigated a range of companies, from Gazprom to Fiat, for anti-competitive practices. In an important talk about the state of the global business, she explains why markets need clear rules -- and how even the most innovative companies can become a problem when they become too dominant. "Real and fair competition has a vital role to play in building the trust we need to get the best of our societies," Vestager says. "And that starts with enforcing our rules."