The following comes from "Advanced Basketball Defense" by Ernie Woods. It is one of the best defensive books I've read in my coaching career. First bought it in 2007 and is one of a handful that I re-read on an annual basis. Here are just a few nuggets:
By using short, descriptive words to teach the various fundamental skills, players will quickly learn to play defense aggressively.
If you are not spending adequate practice time teaching and improving defensive fundamentals, then you are setting up your players and team for certain failure.
Disruptive pressure, like wine, gets better with age.
Defensively, nothing good ever happens on middle penetration -- it's all bad. Dribbling up the middle usually results in a lay-up, drop pass for an easy shot, short pull up jumper or a kick out pass for an open three point shot.
Since players receive instruction from a variety of sources, it is very important that the entire coaching staff use the same offensive and defensive terms.
Be creative and design your own break down drills to fit your needs and player abilities. Creating drills and plays are one of the enjoyments of coaching basketball.
Always introduce a skill or drill one day and refine it.
Defense starts prior to your opponent receiving the ball, not after! (Coach Starkey: one of the most important and difficult principles to teach players)
Do not allow any successful pass over fifteen feet in distance. In allowing uncontested passes over 15 feet, it compromises the defense and opens up the entire court to the offense. It also forces all defenders to make major defensive adjustments and in the process makes them vulnerable to offensive attack.
Helpside support not only eliminates one-on-one isolations, but also provides the defense with a numerical advantage.-