you wouldn't like to say how = you don't have a clue how there are some ways to make a good guess though http://www.schneier.com/blog/archives/2008/07/truecrypts_deni.html www.zdnet.co.uk/news/security/0,1000000189,39448526,00.htm poor mans deniable encryption may be the best after all...boot loader on a USB full drive encrypted and argue that you shredded it so there is nothing to decrypt and the keys you have up don't work anymore but are the most recent keys... In a pure cryptanalysis sense Truecrypts deniability may be near perfect, but when you add an OS and applications etc on top of that you have issues that start to come up.