Here's a question that I never see brought up. For those experienced users who use TrueCrypt hidden volumes, how do you know that the hidden volume is in fact indistinguishable from the rest of the outer volume? I'm asking this especially for the case where different types of encryption are used for the hidden and outer volume. Different algorithms could theoretically yield minor differences. I'm asking for a line of reasoning or a testing procedure that would indicate to you that all hidden volumes are indistinguishable from all outer volumes. If it's a testing procedure, I'd like to know if you've actually tried it or know of someone who has. I've done experimentation in the past, and I do believe that TrueCrypt's claims are in fact correct. But I'm wondering if anyone else actually questions those claims or whether people just basically believe whatever's in the documentation. I've done some Google searches and come up with very little (except for some stuff I've written in the distant past and very few other tidbits here and there). Thanks Edit: I'm asking this question to see if my line of reasoning is similar to other people, and I'm curious about how many people that use TrueCrypt hidden volumes actually ask these types of questions. My reasoning is that the more people that ask these questions, the better off we all are. But, sadly, I'm beginning to feel that the developers basically do everything, including the testing. And we're all just sheep. All these thousands of people that review the source code seem like a myth because most of the people I've talked to know very little outside of what's in the documentation.