The public inquiry into journalistic ethics sparked by the phone-hacking scandal will hear from the company at the heart of the controversy.
Rhodri Davies QC, representing News International, will address Lord Justice Leveson on the second day of the probe into the culture, practices and ethics of the press.
It comes just days after the company's executive chairman James Murdoch was accused of misleading Parliament's hacking inquiry.
During a bruising second appearance before the House of Commons Culture Committee's inquiry, Mr Murdoch insisted he had not learned until recently that the practice of illegally eavesdropping on private phone messages was widely used at the Sunday tabloid.
Mr Davies will be the first representative from a string of news gathering organisations to give evidence before the inquiry. He is to be followed by Jonathan Caplan QC, for Associated Newspapers, and James Dingemans QC, for Express Newspapers.
The inquiry heard from Associated's editor-in-chief Paul Dacre during a preliminary seminar in which he accused David Cameron of a "cynical act of political expediency" by declaring regulator the Press Complaints Commission a failed body.
Their appearance at the Royal Courts of Justice comes after the inquiry heard how private investigator Glenn Mulcaire's notebooks suggested that hacking was not unique to the defunct red top and went beyond one "rogue reporter". Mulcaire's records include references to "the Sun" and "Mirror" while at least 28 News International employees commissioned him to illegally intercept voicemails, the hearing was told.
Lord Justice Leveson's inquiry also heard that police believed News International - publisher of the News of the World - was involved in hacking phones as recently as 2009.
Mulcaire was jailed along with the News of the World's former royal editor Clive Goodman in January 2007 after they admitted intercepting voicemail messages left on phones belonging to royal aides.
The Leveson inquiry, which opened formally on Monday, was set up by Prime Minister David Cameron in July after revelations that the News of the World hacked the phone of murdered schoolgirl Milly Dowler after she went missing in 2002.