Rule 11
Rules in this section apply to vessels in sight of one another.

Rule 12
(a) When two sailing vessels are approaching one another,
so as to involve risk of collision, one of them shall keep out of
the way of the other as follows:

when each has the wind on a different side, the vessel which has
the wind on the port side shall keep out of the way of the other;

when both have the wind on the same side, the vessel which is to
windward shall keep out of the way of the vessel which is to leeward;

if a vessel with the wind on the port side sees a vessel to windward
and cannot determine with certainty whether the other vessel has the
wind on the port or on the starboard side, she shall keep out of the
way of the other.

(b) For the purposes of this Rule the windward side shall be deemed
to be the side opposite that on which the mainsail is carried or, in the
case of a square-rigged vessel, the side opposite to that on which the
largest fore-and-aft sail is carried.

Pretty simple, isn't it?

Most interesting to me is this part:

"when both have the wind on the same side, the vessel which is to
windward shall keep out of the way of the vessel which is to leeward;"

This says if one sailboat is overtaking another and both have the wind
on the same side, then the sailboat to weather is the give way vessel.

This tells me that the overtaking rule where the overtaken vessel is always
the stand-on vessel does not apply to sailboats.

CN