sequence:

The Gale-Shapley Matching Algorithm

...is a solution to the Stable Marriage Problem, in which one group of elements is matched to a second group of elements by some criteria of preference, and must end up in a "stable" configuration of pairs such that there are no two elements that would prefer each other over their current match. One group takes the role of the "proposer", and the other group can reject their offers if they already have a 'mate' who they prefer instead.