The main personalities in the CIA leak dispute:

Joseph Wilson: Former U.S. Ambassador to Gabon. Wilson was asked in 2002 by the CIA to check reports Iraq was trying to acquire uranium for nuclear weapons from Niger. He reported that the allegation was untrue, but President Bush repeated the allegation in his State of the Union speech in January 2003. That July, Wilson wrote "What I Didn't Find in Africa," which appeared in the New York Times.

Valerie Plame: Undercover CIA officer and wife of Wilson.

Robert Novak: Washington Post columnist. A week after Wilson's New York Times piece, Novak wrote in his column that part of the reason Wilson had been given the Niger mission was that his wife recommended him to her bosses at the CIA. It is a crime to reveal the name of an active CIA operative, but it is not known if Novak knew Plame was undercover. Critics of Bush say the White House leaked Plame's name in revenge for her husband's report.

President Bush: Promised in 2003 to fire anyone in his administration found to have been a leaker in the Plame case.

Patrick Fitzgerald: Special prosecutor.

Karl Rove: White House deputy chief of staff, senior political adviser to President Bush. Rove spoke with at least one reporter about Valerie Plame's role at the CIA before she was identified as a covert agent in a newspaper column two years ago, but Rove's lawyer said last week that his client did not identify her by name.

Matthew Cooper: Time magazine reporter. Newsweek reported this week that in 2003 Rove talked to Cooper about Plame but did not identify her by name. Cooper later wrote a story in which he used Plame's name. Cooper had a short conversation with Rove on July 11, 2003, three days before Novak exposed Plame in his column.

Cooper wrote one article raising questions about government officials trying to discredit Wilson behind the scenes. Cooper had indicated he would go to jail rather than expose a confidential source, but he agreed earlier this month to cooperate with the grand jury after getting clearance from his source to testify. (Rove's lawyer said Cooper had been clear to testify all along because Rove had signed a waiver about 18 months ago. The waiver was "reaffirmed" July 6, the day of a hearing to decide whether Cooper and a New York Times reporter would go to jail.)

Judith Miller: New York Times reporter. She was jailed for contempt of court for not cooperating with a federal investigation into who revealed Plame's identity. Miller did some reporting but never wrote a story and refused to identify her source.

Scott McClellan: White House spokesman. In 2003, he dismissed as "ridiculous" allegations that Rove was involved in leaking classified material, but McClellan has recently refused to discuss the case.

Compiled from reports by The Associated Press, The Washington Post and the British Broadcasting Corp.