The first five runners from each team to cross the finish line receive the points that correspond to their place. The first place runner receives one point, the second place runner two, and so on. The team receiving the lowest score wins.
The sixth and seventh runners on a team, although they don't receive a score, can also be important, in that they can "displace" scoring runners from the other team. For example, consider the following race:
Capo Valley Mission Viejo
3rd 1st
4th 2nd
6th 5th
7th 11th
8th 12th
(9th)
(10th)
Final Score: 28 31
Capo Valley wins!
As you can see, even though Capo's sixth and seventh place runners' scores were not added into the total, they were enough to displace the Diablo's fourth and fifth place runners' scores, and give the win to the Cougars.
A score of 27 or less always wins a meet, as does having the first, second and third place winners, with at least five runners finishing. This final instance is called a "sweep".