Zone 101The basic theory behind a zone defense is that each player is assigned a specific area on the court, as opposed to guarding a specific player. This has advantages and disadvantages. One of the benefits of playing zone is that it can be a great equalizer for teams that aren't as quick or athletic. Zones are best at defending the interior of the court -- the area closest to the basket -- and can be an effective way of neutralizing teams with strong post-up players.
On the other hand, most zones can be exploited by good outside shooters, who can simply "shoot over the zone." It's also difficult to generate a lot of defensive pressure and force turnovers with a zone defense, which makes man-to-man a better choice for teams playing catch-up.
Types of Zone DefensesWhile there are nearly as many variations as there are coaches, here's an introduction to "the zone" and how it is usually played.
2-3 ZoneTwo players -- usually the guards -- are positioned on either side of the top of the key. The center is postioned in the paint, with the forwards to his left and right.
The 2-3 is excellent at protecting the paint, but is particularly vulnerable to good outside shooting.
1-2-2 ZoneThe 1-2-2 -- sometimes called a 3-2 -- is a more aggressive form of zone defense. In a 1-2-2, the quickest/best defender will often be positioned at the top of the key, with two other quick players on either side of the foul line (on "the wings"). The center and big forward are positioned on the low blocks.
A 1-2-2 zone is better at defending the perimeter than a 2-3, allowing the player at the top and one on the wing to "trap" -- that is, to defend the ball with two defenders, usually by backing him up against the halfcourt line or sideline. The best way to attack a 1-2-2 is by passing in to the high post -- the spot where the foul line meets the boundary of the lane. That forces one of the players down low to move up, which makes the baseline vulnerable to shooters or penetrators.
1-3-1 ZoneThe 1-3-1 alignment has many of the same strengths and vulnerabilities of the 1-2-2. In a 1-3-1, the defender at the top of the key defends further out towards half-court, and the defenders on the wings move out towards the three-point line. The power forward moves up and is positioned between the two wing defenders, while the center guards the middle in the paint.
Some coaches use a variation on the 1-3-1, in which a smaller, quicker guard takes the position in the paint and is assigned to run the baseline like a maniac and double-team the ball in either corner.
Matchup ZoneA matchup zone is the bastard child of a traditional zone and a man-to-man defense. To simplify what can be a tremendously complicated concept, in a matchup zone, the defender covering the ball handler plays straight man defense, while the rest of the defense stays in a zone alignment.
For more detailed explanations and diagrams, check out The Coach's Clipboard.