"Upstairs, Downstairs" ran for five series from 10 December 1971 to 21 December 1975. The first four series had thirteen episodes each, while the final series had sixteen. Due to an industrial dispute over extra payments for using newly introduced colour equipment, during which broadcasting unions refused to allow their members to use colour cameras, the first six episodes of the first series were shot in black-and-white, and when colour production resumed, the first episode was remade in colour. Two endings were made, which could be shown depending on whether the black and white episodes were broadcast by the channel. The original untransmitted black-and-white version of the first episode is believed to have been wiped.