!!!The Miniseries:
* ApprovalOfGod: Creator/JohnLeCarre cited this as his favourite adaptation of his works, attributing this to his experience collaborating with Creator/AlecGuinness.
* CaliforniaDoubling: The Czechoslovakia scenes were filmed in Scotland, mainly Glasgow, but some additional filming in Aberguthrie.
* CreatorPreferredAdaptation: Creator/JohnLeCarre was so impressed by Creator/AlecGuinness' performance as George Smiley that in later novels he wrote Smiley's characterization to be in keeping with Guinness's performance.
* DawsonCasting: Karla's daughter is supposed to be in her twenties, but the actress playing her in ''Smiley's People'' was in her thirties.
* FakeBrit: Control is played by Canadian actor Alexander Knox.
* FakeNationality: Soviet spymaster Karla is played by none other than '''[[Creator/PatrickStewart SIR PATRICK STEWART]]'''. Not that it matters much, since [[SilentAntagonist he never talks]].
* HypotheticalCasting: Creator/AlecGuinness initially felt he was wrong for George Smiley and asked if Creator/ArthurLowe would be more fitting.
* IWantYouToMeetAnOldFriendOfMine: The cast of ''Smiley's People'' includes Creator/MichaelGough, who was also in Guinness' films ''Film/TheManInTheWhiteSuit'' and ''The Horse's Mouth''.
* TheOtherDarrin: Due to Creator/MichaelJayston being unavailable to repeat the role of Peter Guillam for ''Smiley's People'', it was recast with Michael Byrne.
* PlayingAgainstType: This was a rare dramatic role for Creator/BerylReid, who was known for light comedy. Creator/AlecGuinness was initially opposed to her casting, but she won him over.
* TroubledProduction: The series was plagued by a series of strikes. Due to shooting overruns, a large number of actors moved to other projects without finishing their roles. Creator/AlecGuinness ended up being on call for eighteen months.