There are three primary rituals performed by LDS temple-goers: Baptism, Initiatory, and Endowment. Mormons believe that these three ordinances are required for salvation, *but* that those who did not participate in them aren't necessarily damned. A faithful LDS member can take the name of a person who has passed away to the temple, and go through the rituals "on behalf" of the person who has died. Baptisms for living LDS members are typically performed in normal church buildings, not in temples, and the ritual is very similar to that of other religions who baptize by immersion. The main difference is that in the temple, the individual is baptized multiple times in succession "on behalf" of those who are dead. The other two ordinances are only performed in temples. The first time an individual attends the temple, he or she participates in the ordinances for himself or herself; all subsequent times the person participates on behalf of someone else. The Initiatory is a ceremonial anointing that takes only a few minutes; the Endowment is an hour-long (usually video) presentation about Adam and Eve, followed by some ritualistic covenants or promises, e.g. regarding chastity and dedication to the church. The full text of these rituals can be found online, for example here: http://www.lds-mormon.com/veilworker/rituals.shtml but most Mormons consider the ceremonies sacred and have promised not to discuss them outside of the temple, so please be considerate. (copy-pasted from this question: http://www.answerbag.com/q_view/587617)