Kevin Pelton over at Basketball Prospectus has a fascinating Q & A session with Tom Thibodeau. You should all check it out; it's an interesting read. Some quotes to whet your appetite:
KP: How much does it help you to have the star players buy in to the importance of defense?
TT: That's the big thing, I think. From day one, Doc sold the vision about how important defense was going to be. Kevin, Ray and Paul have been terrific carrying that vision out. I think when your three top players practice hard every day and commit to doing it, I think it leads to everyone else following it. We have experienced veterans that have also come from very good defensive teams. When you look at a Posey and an Eddie House, those guys are committed to playing strong defense. Then when you look at a guy like [Kendrick] Perkins, who oftentimes gets overlooked--his size and his ability to shut down the lane is critical. Rondo, his ability, his quickness is so important for us.
KP: How do you evaluate a defense?
TT: You're constantly evaluating your defense in terms of one, your ability to get back and your floor balance; you don't want to give up easy baskets. Then you want to keep the ball out of the paint. Then you want to evaluate whether you're challenging shots properly, whether you're rebounding the ball well enough. Then you look at your schemes to make sure that you're executing those things correctly. It's a constant battle, because you can't work on everything but you're trying to build all those habits that make you have a consistent defense. You're always working defensive transition, pick-and-roll defense, low-post defense, one-on-one defense. It comes down to the basic premise of keeping the ball out of the paint. We feel if you take easy baskets away and force teams to shoot contested twos, then you're going to have a good defense.
There's plenty more, including thoughts on KG, Big Baby, and strategy going into the playoffs. It's all great stuff. (Hat tip to BleedingGreen at RealGM for posting this first.)