Anonymous matching is a matchmaking method facilitated by computer databases, in which each user confidentially selects people they are interested in dating and the computer identifies and reports matches to pairs of users who share a mutual attraction. Protocols for anonymous matchmaking date back to the 1980s, and one of the earliest papers on the topic is by Baldwin and Gramlich, published in 1985. From a technical perspective, the problem and solution are trivial and likely predate even this paper. The problem becomes interesting and requires more sophisticated cryptography when the matchmaker (central server) isn't trusted.