- Accidentally Correct Writing: Some situations were conceived as fiction, but were later revealed to have real-life counterparts. For example, "The Compassionate Society" depicts a hospital with five hundred administrative staff but no doctors, nurses or patients. Jonathan Lynn recalls that "after inventing this absurdity, we discovered there were six such hospitals (or very large empty wings of hospitals) exactly as we had described them in our episode."
- Actor-Shared Background: Hacker, Sir Humphrey, and Bernard share birth dates (and dates of death where applicable) with the actors who portrayed them.
- Big Name Fan: Armando Iannucci loves the series. It was while he was presenting the case for it being Britain's Best Sitcom, he was inspired to create his own political comedy series.
- ...But I Play One on TV: When Paul Eddington visited Australia during the 1980s, he was treated as a visiting British PM by the then Australian leader, Bob Hawke, who was a fan of the show. At a rally, Hawke said "You don't want to be listening to me; you want to be listening to the real Prime Minister", forcing Eddington to improvise.
- Dawson Casting: Bernard's age is never stated on screen, but various hints suggest he's supposed to be a fairly young rookie civil servant, probably in his late twenties, much younger than Derek Fowlds at the time.
- Doing It for the Art: Nigel Hawthorne was required to perform some of the most convoluted Sesquipedalian Loquaciousness ever brought to screen, big or small. However, in spite of being forced to perform lines like: "The relationship, which I might tentatively venture to aver has been not without some degree of reciprocal utility, and perhaps even occasional gratification, is emerging a point of irreversible bifurcation and, to be brief, is in the propinquity of its ultimate regrettable termination.", he never once resorted to using a cue card, but insisted on actually learning his lines (although he briefly took beta blockers to deal with the anxiety). The writers were shocked and awed.
- Harpo Does Something Funny: Or in this case, as writer Jonathan Lynn reports putting in the margins of scripts, "Paul doesn't have to say this line if he doesn't want to". Paul Eddington, who played Hacker, had an amazing ability to convey the same sense a line was intended to give with an expression. One particularly good example is 1:10 to 1:30 or so in this clip.
- The Shelf of Movie Languishment: The Pilot, "Open Government", was produced in 1979 but not transmitted until 1980 in fear that it could influence the results of the 1979 UK General Election.
- Throw It In!: The moment in "The Official Visit" where Bernard's briefcase falls open and lets his files spill out on the station platform was unscripted — in fact, Derek Fowlds actually said "oh, shit!" when it happened, which somehow made it into the finished episode (probably because it was only just audible over the noise of the trains).
- Not surprising; Derek always said "shit" every time he goofed.
- Wag the Director: Paul Eddington, a firm believer in nuclear disarmament, once convinced the writers to rework the script of a Yes, Prime Minister episode that he believed was rather too flippant about nuclear war.
- Written-In Infirmity: In Yes, Prime Minister you might notice that in the later episodes especially, Jim Hacker spends much of the show sitting still behind his desk or in his armchair at home. This is because at the time of filming, Paul Eddington was in the early stages of the T cell lymphoma that eventually killed him, and the episodes were written to be as comfortable for him to perform as possible.
Trivia / Yes, Minister