The first witness is expected to be called today in the perjury trial of former News of the World editor Andy Coulson.
The 47-year-old is accused of lying during the trial of former socialist MSP Tommy Sheridan at the High Court in Glasgow in 2010.
Coulson, a former director of communications for the UK prime minister, denies the allegations against him.
His trial got under way at the High Court in Edinburgh on Friday with the selection of 15 jurors and the reading of some agreed evidence.
The nine men and six women of the jury are due to hear from the first witness today.
Judge Lord Burns has already warned the jurors they must try the accused “solely and exclusively” on the evidence they will hear during the trial.
Prosecutors allege that Coulson, from Kent, made false claims on December 9 and 10 2010 after being sworn in as a witness at Mr Sheridan’s perjury trial.
Among the claims, it is alleged that Coulson falsely stated that, before the arrest of private investigator Glenn Mulcaire and News of the World journalist Clive Goodman in 2006, he did not know that Goodman was involved in phone hacking with Mulcaire.
The trial could last around four weeks.