Maybe I’m an atypical case, but my polygraph with the CIA did not ask a single question about my sexual history/practices/preferences/etc.  I do believe these polygraph sessions are fairly flexible, depending on polygrapher, applicant, etc., and vary from case-to-case accordingly.  So, TimothyLeary, maybe you’ll get lucky and won’t be asked about your sexual history.

TimothyLeary,

 No, I am not kidding !  The polygraphers will use all
sorts of tricks, and one should think very deliberately,
before answering any questions.  One's sex life is none
of their business, and I believe, they can not ask about
it, until the "door is opened", to that subject.   I ran into
a number of NSA employees, who were very sexually
oriented (including women); images of porn were
everywhere.  The NSA polygraphers' behavior should be
an indication, to anyone applying there, just how
messed up of a place it is.  If they denied clearances,
based on the activity you mentioned, very few NSA
employees would hold clearances...

NSAReject,

" As I stated before, my NSA  polygrapher said that he
masturbated to porn on the Internet (a ruse to get me
to admit to it).  Let this experience be a warning to all."

You've got to be kidding! Will they deny security clearance because of that? If so they must only have enuchs and 80 year-olds who can't afford viagra working for them.  If they ask me that question I'm going to tell them "hell yeah!" and then give them a rundown of my top 3 favorite sites. Ridiculous.

Thanks for the advice and support.  Unfortunately the agency I work for does not have an appeals process which allows for court review.  I'll post more on my experience as the process unfolds and provide more details.  If it weren't so serious I'd laugh at how absurd this is.

polyrized,

  Sorry, to hear about your experience with the CIA's
polygraph.  Here is a clear example how derogatory
information is sent to other agencies (e.g., NSA to
DoD/DSS), and how this can affect current clearances.
My last full-scope poly was in the 1990s and I will never
take one again (I guess, I have grown past it).  It is
amazing that Intel agencies think that one's sex life
is their business, and that applicants let it be so.  As I
stated before, my NSA  polygrapher said that he
masturbated to porn on the Internet (a ruse to get me
to admit to it).  Let this experience be a warning to all.

polyrized: If you have a DoD clearance and it gets
revoked, you can hire a lawyer and fight in the DoD's
appeals court (you will get a statement-of-reasons,
SOR, from the DoD Department of Hearings and Appeals,
DOHA).

I found out that the CIA divulged to another federal agency information about my sexual history from my polygraph ten years ago.  This was without my knowledge or consent and despite their verbal assurances all the information would be kept private.

I did not engage in any illegal or nonconsensual behavior.  But this was very sensitive information.

So let this be a warning that when they tell you they will keep the information private, they lie.  And that even years later it can be given out even when it concerns the most intimate and private acts.  As far as I can tell I don't even have any legal recourse.