The title music, "The Edwardians", was specially composed for the series by Alexander Faris. Two different themes were used: a slower waltz-time theme, normally over the opening titles, and a faster jaunty polka theme over some of the end-credits, though the waltz theme was used for the end-credits of episodes that ended on a sombre note such as the news about the sinking of the Titanic. The polka theme was set to lyrics by Alfred Shaughnessy and sung as a bawdy song "What are we going to do with Uncle Arthur?" during a music hall act by Sarah (Pauline Collins) in the episode Upstairs, Downstairs: For Love of Love (1972).
By season 3, 165 Eaton Place consisted of: 6 bedrooms, 2 bathrooms, dressing room, dining room, drawing room, morning room, library, study, and another room which changed from gaming room to whatever the family needed.
Rachel Gurney loathed her character (Lady Marjorie) and was written out of the series at her own request. This was achieved by having her make a journey to Canada on the ill-fated maiden voyage of Titanic.
Gordon Jackson (Hudson) appeared in 60 of the series' 68 episodes, more than any other actor. In second place is David Langton (Richard Bellamy), who appeared in a total of 56 episodes. The only other actors to appear in 50 or more episodes were Jean Marsh (Rose Buck) and Angela Baddeley (Mrs Bridges), who appeared in 54 and 52 episodes respectively.
A LWT executive viewing the first season for the first time thought the show was a complete disaster and had no hope in the ratings. Consequently it was left on the shelf for several months and finally got its first ever screening after 10pm on a Sunday night in the UK.