An arranged marriage was a wedding arranged by a person or persons other than those being married. Arranged marriages can take place with the participants' prior knowledge or agreement or without it, depending on the circumstances, context and the culture of those arranging the marriage. Often, the arrangements will be made by family members on behalf of their children as part of their culture, but such marriages may also be orchestrated for political reasons. Some considered these unions akin to prostitution. (TNG: "The Perfect Mate") According to Trip Tucker, arranged marriages disappeared on Earth when slavery did. (ENT: "Breaking the Ice")
The Vulcans conducted arranged marriages, although they did not always proceed as planned. (TOS: "Amok Time"; ENT: "Breaking the Ice", "Home")
In 2364, Deanna Troi was to be married to Wyatt Miller, to whom she was bonded as a child by both of their respective families. (TNG: "Haven")
In 2368, the Kriosian Kamala was to be married to Alrik of Valt Minor as a means to end a centuries-long conflict. Beverly Crusher was critical of Jean-Luc Picard for handing her over to be essentially prostituted. When Picard explained that she knew what she was doing, Crusher countered by saying she'd been conditioned to accept it. (TNG: "The Perfect Mate")
In 2373, Ensign Vorik realized that his arranged marriage on Vulcan was unlikely to take place due to his disappearance in the Delta Quadrant, and his intended had probably chosen another mate. He then proposed marriage to B'Elanna Torres. (VOY: "Blood Fever")