Dec. 16, 2002 - President Bush appoints former New Jersey Gov. Thomas Kean to chair the Commission.

March 31 - April 1, 2003 - First public hearings take place. The focus is hearing from victims and people impacted by 9/11.

May 22 - May 23, 2003 - Second public hearings take place. The focus is congressional oversight and aviation security.

July 8, 2003 - The first interim report is released.

July 9, 2003 - Third public hearing takes place. The focus is "Terrorism, Al Qaeda, and the Muslim World."

Sept. 23, 2003 - The second interim report is released.

Oct. 14, 2003 - The fourth public hearing takes place. The focus is intelligence and national security policy.

Nov.19, 2003 - Fifth public hearing. The focus is emergency preparedness.

Dec. 8, 2003 - Sixth public hearing. The focus is "Security and Liberty."

Jan. 26 - 27, 2004 - The seventh public hearings take place. The focus is border and aviation security.

March 24, 2004 - Former counterterrorism chief Richard A. Clarke testifies.

March 30, 2004 - The White House says it will allow National Security Adviser Condoleezza Rice to testify publicly before the commission investigating the September 11 terrorist attacks, so long as her appearance is not considered a precedent.

April 8, 2004 - Condoleezza Rice testifies in the morning - public and under oath. Former President Bill Clinton testifies in the afternoon. Clinton's testimony is not public or under oath.

April 9, 2004 - Former Vice President Al Gore has a three-hour private meeting with the commission. A press notice describes the Gore as "candid and forthcoming."

April 13, 2004 - Former FBI Director Louis Freeh, Former Attorney General Janet Reno and current Attorney General John Ashcroft testify at tenth public hearing. Former acting FBI Director Thomas Pickard and J. Cofer Black, former head of the CIA's counterterrorism center, also testify.

April 14, 2004 - CIA Director George Tenet and FBI Direct Robert Mueller testify in separate public sessions.

April 29, 2004 - President George W. Bush and Vice President Dick Cheney meet with the 9/11 Commission from 9:30 a.m. until 12:40 p.m., in the Oval Office at the White House. The president and vice president answer questions but are not under oath. The meeting is not officially recorded. Two members of the White House counsel's staff are allowed to take notes during the session, as are the commission members.

May 19, 2004 - Former New York City Mayor Rudy Giuliani and former director of New York City's Office of Emergency Management Jerry Hauer testify before the 9/11 Commission.

May 27, 2004 - Original deadline to report on its findings.

June 16, 2004 - Commission holds its twelfth and final public hearing on its investigation into the Sept. 11 attacks.