The shooting circle — universally known as "the D" because of its shape — is the most important zone on a field hockey pitch. Per the International Hockey Federation (FIH) Rules of Hockey, it is formed by a quarter-circle of radius 14.63 metres (16 yards) drawn from each goalpost, connected by a straight line parallel to the backline. Goals can only be scored if the ball is played by an attacker while it is wholly or partly inside this circle — a shot from outside the D does not count, even if it crosses the goal line.

The penalty spot sits 6.4 metres (7 yards) from the centre of the backline, directly in front of the goal, and is used for penalty stroke awards. For a penalty corner — awarded for a defensive infringement inside the circle or backline — the ball is placed on the backline at least 10 metres (11 yards) from the nearer goalpost, with one attacker (the injector) pushing or hitting it into play.

The shooting circle's shape fundamentally defines field hockey tactics: because shots from outside the D do not count, teams must work the ball into this zone before attempting goal — making circle penetration and defending the D the central tactical battlegrounds of the sport. The 23-metre line, which lies further out, defines a broader attacking zone where certain restart rules apply, but only the D itself governs where a goal can legally be scored from.