Top 11 Methods of Interrogation - Listverse.
What I consider torture is beatigns, shaking, rape, maiming, random executions and such. There was an Israeli intelligence officer who had developed a quite successful interrogation technique. After weeks of being interrogated by Israeli intelligence, the subject was then moved into general population of the jail where they where being held. The jail itself was completely bugged but had several listening devices that where meant to be found, this gave the prisoner a feeling of security in that they thought there where areas of th jail that they could talk without being overheard. Another important part was that the jail itself where filled with willing prisoners that where working for the Israelis. They would greet the released prisoner and apploud them for withstanding the interrogation, and after a while would get out of the prisoner what he had told the Israelis during interrogation, and many things that where held back.
Sadly there is no magic pill that will instantly turn someone into a truth telling machine (damn movies lied to me). But the combination of stressing a prisoner then providing them with a semblance of security has shown to work well. All of these methods do take time though.