I usually go with cold readings - though we give our local libraries copies of the script that people can check out and read and become familiar if they're interested.

I like monologue auditions, but, frankly, I've discovered that asking for a monologue scares away all but the most seasoned...and even a few of them.

I do like to have call backs, so I can see if somebody who does a good cold reading can improve at all - or if that good audition was their little flash in the pan. I know from personal experience: I am a very good auditioner - usually much better than I am in performance LOL.

I agree with tristan. I use the cold reading simply because that is what our area actors are used to.

Thanks for the imput. Auditions went really well, we did use cold reads. However, before starting the reads I had them do a warm up. I wasn't sure about this because I didn't want to make anyone uncomfortable or think "what the #*@$ is this girl doing? ...;p So it was very simple just to get everyone moving and vocal before we started. We did the wave. It was a hit! In fact one person, as they went onstage to read even said, "Can we do the wave again, I need to loosen up."

I think monologues are kind of a waste of time. I like to work with the material at hand, and maybe provide suggestions to see how an actor responds to direction.

At our CT we use cold readings almost exclusively (I don't remember the last time one of our directors wanted monologues!).  We also do them all as a group -- that is, all the auditioners are assembled, and the cold readings are done between the auditioners; the SM or other person reads in parts only if there's no one available.

Yes, if I go second, third, or last, I get to benefit from seeing/hearing the other actors' auditions, so that my reading can be all that much better.  To compensate for this, when I'm the director, I always give the actor who does the FIRST cold reading the option of re-reading the same bit at the end after everyone else has.

The only disadvantage of this:  great actors who are terrible cold readers.  One of our best and long-time actresses falls into this category.  I'm afraid that a newbie who's like this may get overlooked for a part that he/she would do a wonderful job of.

Yes, some of our directors do call-backs, but not that often.  Most of them have gotten into the habit of casting after 2 or 3 nights of such open group cold reading audition sessions.