US President George Bush has signed into law a far-reaching overhaul of the country's intelligence agencies.
President Bush says the new measures will better protect the US
The new measures - the most sweeping changes in nearly 60 years - are intended to prevent a repeat of the 11 September attacks.
They will lead to the creation of a national intelligence director to oversee the work of the 15 US security agencies, including the CIA and FBI.
Intelligence officials will also be granted greater surveillance powers.
"Our vast intelligence enterprise will become more unified, co-ordinated and effective," Mr Bush said at the signing ceremony.
"It will enable us to better do our duty, which is to protect the American people," he added.
Under the new law, a single individual will be put in charge of co-ordinating the work of the country's spy agencies, as well as their multibillion dollar budgets.
"A key lesson of 11 September is that America's intelligence agencies must work together as a single, unified enterprise," Mr Bush said.
US INTELLIGENCE BILL
Establishes director of national intelligence
Creates a national counter-terrorism centre
Sets up a civil liberties board
Increases border patrols
Tightens visa requirements
Strengthens rights to investigate terror suspects
A national counter-terrorism centre will also be created.
The law will allow operatives to place wiretaps on suspected terror suspects and to improve the efficiency of baggage-screening equipment at borders and airports.
The legislation was the result of the year-long investigation by the bipartisan 9/11 Commission into the 11 September 2001 terror attacks on New York and Washington.
The inquiry found the country's intelligence agencies failed to share information and were often engaged in bureaucratic competition.
Such weaknesses, it concluded, were partly to blame for the failure to prevent the attacks in which nearly 3,000 people died.