Ian G -
I agree. For me, it was a huge plus having access to a top-notch art school where I could take classes that involved working with the human figure. Having other photographers around with prior experience, plus a terrific instructor, made it easy to learn how to interact with a model, how to pose and direct them, and of course, build up a quality, edited portfolio. That makes it all the easier to approach models you haven't worked with before. Now that I've got experience and the confidence in my own work and vision, it's much easier to deal with folks, and you relate to them on a personal-yet-professional level which makes the shoot go so much easier.
For those who don't have access to/can't afford a whole semester class at a community college, try a weekend workshop. There are tons of them offered all over the place, so ask around if anyone you know has attended the workshop before and knows the instructor. Having a good instructor who has a quality portfolio of their own, with a clear philosophy behind their work, is a huge plus and will make all the difference, even if you find that you don't agree with the way they do things.