"Parallels" is the 11th episode of the seventh season of the American science fiction television series Star Trek: The Next Generation, the 163rd overall. It was originally released on November 29, 1993, in broadcast syndication. The episode was written by Brannon Braga, and directed by Robert Wiemer. Executive producer Jeri Taylor wrote the final scene of the episode, but was uncredited.

Set in the 24th century, the series follows the adventures of the crew of the Federation starship Enterprise. In this episode, Lt. Worf (Michael Dorn) returns from a bat'leth tournament and slowly discovers that he is being moved across parallel universes. The crew of an alternative Enterprise realise what is happening and seek to return him to his own reality, but, after an attack by a Bajoran ship, a space-time fissure explodes, causing hundreds of thousands of alternative versions of the Enterprise to enter the same universe. After Worf reverses the course through the fissure, he and all the versions of the Enterprise are returned to their respective universes.

Braga intended to focus the "Parallels" on Jean-Luc Picard (Patrick Stewart), but this was changed to Worf. The change was made in order to make the differences more obvious across the timelines, as Braga worried that Picard's relationships could not significantly differ across near-universes. The producers were concerned with the confusing nature of the initial proposal, but felt that further changes greatly improved it. Wil Wheaton appeared as Wesley Crusher, replacing the initial plan to include Tasha Yar, after Braga was concerned about copying "Yesterday's Enterprise". "Parallels" received Nielsen ratings of 12.8 percent, one of the highest for the season, but some fans were upset at a Worf/Deanna Troi romance. Critics responded favorably to the episode, with praise directed at both Dorn and Marina Sirtis.

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