The National Commission on Terrorist Attacks Upon the United States, also known as the 9/11 Commission, was set up on November 27, 2002, "to prepare a full and complete account of the circumstances surrounding the September 11 attacks", including preparedness for and the immediate response to the attacks. The commission was also mandated to provide recommendations designed to guard against future attacks.
Chaired by former New Jersey Governor Thomas Kean, the commission consisted of five Democrats and five Republicans. The commission was created by Congressional legislation, with the bill signed into law by President George W. Bush.
The commission's final report was lengthy and based on extensive interviews and testimony. Its primary conclusion was that the failures of the U.S. Central Intelligence Agency (CIA) and Federal Bureau of Investigation (FBI) permitted the terrorist attacks to occur and that if these agencies acted more wisely and more aggressively, the attacks could potentially have been prevented.
After the publication of its final report, the commission closed on August 21, 2004. The commission's website was shut down, but has been archived.