Series creator Buddy Ruskin, a former Los Angeles police officer, used his experiences with a special L.A.P.D. youth squad as the basis for this show.
When the series premiered, Clarence Williams III was 29, Michael Cole was 28, and Peggy Lipton was 22.
At the end of every episode, the camera pulls back as the Mod Squad walks off in one direction.
The "Woody", a 1950 Mercury wood paneled station wagon, was wrecked in The Death of Wild Bill Hannachek (1969). At the end of the episode, the Squad watches their "old buddy" burn, and Linc utters the classic line, "Good bye, old paint". In the reunion movie, "The Return of Mod Squad (1979)," Pete is rich, so he buys a woody when the three of them unite for the task of finding the bad guy.
During a 1995 interview with Terry Gross on the National Public Radio program "Fresh Air", Clarence Williams III poked a bit of gentle fun at the formulaic nature of some of the show's plots: "I could always tell when the writers were having difficulty coming up with a different show for us. Because they would always bring out the old chestnuts. Well, there's two chestnuts you would bring out when the writers were having a little trouble. One is that the police commissioners complain to Captain Greer that these young kids are running around. So you'd do that show about two times a season. And then toward the end of the year when we're running low on funds because a few of the shows would go over budget, there'd always be some kind of murder at a theatrical studio, so we could shoot one on the lot without going on location. So always some movie star who got knocked off, or some makeup person who got knocked off, and the Mod Squad was brought in undercover, and so we'd wind up being a grip or a makeup person, or something or other, or a script supervisor, and we'd solve the case. Because that meant we could not go off the lot for that particular episode, because we [usually] used to shoot four days off and three days in."