"Journey to Babel" is episode No. 39, production No. 44, of the second season of the original science fiction television series, Star Trek. Written by D. C. Fontana and directed by Joseph Pevney, it was first broadcast on November 17, 1967, and was repeated on July 5, 1968.

In this episode, the Enterprise must transport dignitaries to a peace conference, with an assassin on the loose. It features the first appearance of Sarek (Mark Lenard) and Amanda (Jane Wyatt), parents of First Officer Spock, as well as the first appearance in the series of two other alien species, the Andorians and the Tellarites. Wyatt had been widely known for the 1950s sitcom Father Knows Best, where she played Elinor Donahue's mother. On the previous Star Trek episode, Donahue was the guest actor, playing Commissioner Nancy Hedford, who became Zefram Cochrane's "Companion".

On stardate 3842.3, the starship USS Enterprise, under the command of Captain James T. Kirk, is transporting Federation ambassadors to the Babel Conference to discuss the admission of the Coridan system into the Federation. The system is a prime source of dilithium crystals but is also underpopulated and unprotected. Mining rights are disputed by many warring species who have strong reasons for keeping Coridan out of the Federation.

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