According to the May 30. 2005 Bradbury memo, the CIA has used “enhanced techniques to varying degrees” in the interrogations of 28 detainees.
The CIA “used the waterboard extensively in the interrogations of KSM (Khalid Sheikh Muhammed] and Zubaydah [Abu Zubaydah], but did so only after it became clear that standard interrogation techniques were not working. Interrogators used enhanced techniques in the interrogation of al-Nashiri with notable results as early as the first day.”
But don’t worry, they didn’t really hurt.
The memos say that medical and psychological professionals from the CIA’s Office of Medical Services evaluate the detainees to ensure that the detainee “is not likely to suffer any severe physical or mental pain or suffering as a result of interrogation.”