> I haven't been to such an event before, the "Black Tie Preferred",
>how strictly is this followed?

Funny you should ask. I was just going to post asking the same thing.
I plan to wear a black suit and hope that will be good enough. I
doubt
they will throw anyone out for not being in a tux. ;-)

Did you get the email from the conference chairman, Mr Goetz, last
week? He said they were trying to work out a deal with a clothier in
the area so attendees could pick up a tux prior to the event and
return it the next morning. That seems like it would be a logistical
problem. I just don't think it is necessary either. It hasn't been
mentioned again so maybe the arrangement didn't work out. I am hard
to
fit anyway. ;)

I have been to a few political banquets in nice DC hotels where the
president or vice president of the U.S. have been on the dais and
business attire was acceptable. Hopefully that will be the case with
ISDC.