The Official Rules of the World Lawn Dart Federation

1) The playing field must be grassy flat surface clear of
stones and other obstructions, and the target areas must be
such that a lawn dart, dropped from a height of 3 feet will
stick in the ground.

2) Target Circles are no more that 16" in diamter and are
separted by a distance of no less than 15 Royal Strides (~35ft).
Once the target circles have been positioned at the beginning
of a match, they cannot be physically moved by players (i.e. if a
circle moves due to a lawn dart striking it, it "stays where
it lays". The circle is used (alternately) as both the throwing
area and the target.

3) 4 darts (two red, two yellow) are used.

4) For singles, the opposing players play together, each
throwing two darts from one target circle to the other.
Throws alternate: player1, player2, player1, player2.
An End is completed after the four darts are thrown and scored.
The players then play from the opposite circle and alternate
between the circles for the balance of the match.
For doubles, a player from each team is stationed at each circle
and the players alternate throwing darts.

5) Assignment of dart color (red or yellow) is determined by draw.
The Red player(s) get to throw "first dart" at the beginning of a
match. After the first End, the first dart in an End is thrown
by the team who won the previous End.

6) The dart may be thrown in any manner. However the thrower's
feet must remain behind the circle. It should be noted that
high "ARC" (the parabolic path travelled by a thrown dart) is
the hallmark an accoplished player.

7) The dart tip must be embeded in the ground to score. Darts
which do not penetrate the ground are "dead" and do not score.

cool Darts (including Dead darts) may not be removed from the
playing field until the end is completed and the score is tallied

9)Scoring of an end is as follows:
Only one team scores (wins) an end
The team with "closest dart(s)" to the target circle score
A dart inside the target circle scores 3 points
A dart within 1 dart length of the circle scores 1 point

Examples:

Red dart 1 is closest
Yellow dart 1 is next closest
Red dart 2 follows, Yellow dart 2 is farthest
Red team scores 1 point

Red dart 1 is closest
Red dart 2 is next closest
Yellow dart 1 follows, Yellow dart 2 is farthest
Red team scores 2 points

Red dart 1 is in the circle
Yellow dart 1 is closest
Red dart 2 follows, Yellow dart 2 is farthest
Red team scores 3 points

Red dart 1 is in the circle
Red dart 2 is closest
Yellow dart 1 follows, Yellow dart 2 is farthest
Red team scores 4 points

Red dart 1 is in the circle
No other dart is in scoring distance (1 dart length)
Red team scores 3 points

Red dart 1 is in the circle
Yellow dart 1 is in the circle
Red dart 2 closest, Yellow dart 2 is farthest
Red team scores 1 point (darts in the circle cancel each other)

Red dart 1 is in the circle
Yellow dart 1 is in the circle
Red dart 2, Yellow dart 2 are not close enough to score
This is a "Dead End" and neither team scores

Red dart 1 is in the circle
Red dart 2 is in the circle
Yellow darts are outside the circle
Red team scores 6 points

Red dart 1 is in the circle
Yellow dart 1 is in the circle
Red dart 2 is in the circle, Yellow dart 2 is outside the circle
Red team scores 3 points (darts in the circle cancel each other)

All 4 darts are in the circle
This is a "Dead End" and neither team scores

10) The match is won when a team reaches or exceeds 21 points
and exceeds their opponents score by 2 points. If a team
reaches or exceeds 11 points before their opponents score,
that team wins (this is a "skunk").