Nadav Kander on Portraiture
Settle in for an outstanding 13 mins on the philosophy of portraiture from one of the most interesting portraitists working today. (If you are not familiar with the work of Nadav Kander, you may want to take a look at his website [some NSFW] first.)
Produced by the National Portrait Gallery as a tie-in to the 2012 Olympics, this is by far the most detailed look I have yet seen into how Kander works. As a bonus, there are several still BTS shots showing his portrait sets.