Glenn Greenwald is a former lawyer, journalist and star blogger of the US edition of the Guardian newspaper. He will always be remembered as the journalist behind the revelations by Edward Snowden. He first met the man who a few days later became the most famous whistleblower in history in a tiny Hong Kong hotel room in May 2012. Snowden handed over to the American journalist tens of thousands of classified documents that showed the extent of the surveillance practices of the British and US intelligence services. Working alone from Rio de Janeiro, Greenwald shook the world’s most powerful nation and its British allies to their foundations. US President Barack Obama and Britain’s prime minister, David Cameron, were publicly confronted with evidence of the abuses carried out by their intelligence services. They were faced with a diplomatic firestorm and an outcry from activists and campaigners for a free Internet. It was largely thanks to Greenwald’s work that the Guardian US was awarded the prestigious Pulitzer Prize for “its revelation of widespread secret surveillance by the National Security Agency” and for sparking “a debate about the relationship between the government and the public over issues of security and privacy”.