!! In the TV series:
* TheDanza:
** In a weird sideways manner. The character "Natalie" was based on Mindy Cohn, who at the time was not an actress but a student at a school the producers visited for ideas and inspiration. She was invited to audition, and ended up cast essentially as herself.
** Creator/GeorgeClooney as George Burnett during the 1985 and part of 1986 seasons.
** Molly Ringwald, during her one season stint (the first one; 1979-1980) played Molly Parker.
** Not to mention Geri Jewell as Cousin Geri.
* DisabledCharacterDisabledActor: Geri Jewell, who played Geri, actually has cerebral palsy.
* DyeingForYourArt: Lisa Whelchel's hair was dyed blond for the role of Blair (during her [[MickeyMouseClub New Mickey Mouse Club]] run, her hair was a dark brunette). [[LampshadeHanging Lampshaded]] periodically to imply the character's hair is not naturally blond either.

* HeyItsThatGuy: Lots, but most notably Kenneth Mars in the episode "Gossip".
** Natalie wound up voicing Velma in ScoobyDoo.
** Mayim Bialik (the future Blossom and Amy Farrah Fowler), Seth Green, and Juliette Lewis in the finale
** A very young Helen Hunt in a first-season episode
** Creator/GeorgeClooney had feathered hair!
** {{MacGyver}} is Tootie's uncle! With [[Series/GoodTimes Willona]] as his mother-in-law. Including a ''ShoutOut'' to TheJeffersons, when she says "You're moving on up." Ja'net Dubois sang the "Moving on Up" theme.
** Jo was [[SonnyWithAChance Sonny Munroe's]] mom!
** Alex Rocco aka [[TheGodfather Moe Greene]] played Jo's father!
** LaurenTom played exchange student Miko!
** Kelly, a latchkey thug living down the street, was a temporary Cousin Oliver. Played by [[HeyItsThatGuy Pamela Adlon]], Marcy from Californication.
* IAmNotSpock: Nancy [=McKeon=] didn't come back for the interview, in part because of her commitment to TheDivision, and in part because she did't want to be TypeCast as Jo anymore.
* TheOtherDarrin: Blair Warner's mom is played by a different actor in Season 3 than was used in Season 1 and no explanation was given.
** Natalie's boyfriend Snake, a.k.a. [[spoiler: Norbert]]
* WhatCouldHaveBeen: Despite the number of main characters being thinned between Seasons 1 and 2, production expressed interest in retaining Molly Ringwald as a regular. However, she left to pursue a movie career.