A handful of senior al Qaeda prisoners held by the Central Intelligence Agency in secret prisons, including Khalid Sheik Mohammed, were subjected to water boarding in an effort to get information about terror plots against the United States.
The technique has not been used against any prisoners in the last couple years. Other coercive techniques -- such as stress positions and sleep deprivation -- can still be used.
Officially, the CIA never admitted it used water boarding. Therefore it also refuses to say whether it has been banned.