Jury selection has begun in the trial of Rebekah Brooks and Andy Coulson for charges linked to phone hacking and alleged corrupt payments to public officials.
Former News International chief executive Brooks and ex-government spin doctor Coulson, both 45, appeared at the Old Bailey for the first day of proceedings that could take up to six months.
A panel of around 80 potential jurors were brought into wood-panelled court 12 at around 12.30pm.
Mr Justice Saunders told them: "The trial which we are about to start will take a considerable length of time. It is estimated that the case may last until Easter. I hope that with the assistance of counsel the case will finish more quickly, but people who sit on it should be prepared for the case to go on that long."
Seats had to be removed from the courtroom to allow the potential jurors to fit into the space.
The judge added: "To sit on a jury for this length of time, five or six months, is a significant disruption in people's lives and we do appreciate that. We do need the assistance of members of the public like you to try this case. It is, as you will hear, an important case and we have to find a jury able to try it."
He told them that jury service "is a public duty and is not voluntary".
The potential panel members had already filled in a questionnaire, and today were also asked if they can commit to a trial of this length.
Mr Justice Saunders added: "It's critical to the jury system ... that a jury takes the case free from any preconceptions. From now on you do not discuss the case with anyone."