The majority of the episodes were filmed at The London Studios, but in the show's later years, the now-closed (and demolished) Granada studios in Manchester were also used, as well as the now-closed (and also demolished) Meridian studios at Northam, Southampton.
During its run, the series has had three main producers: Paul Smith (1977-1984), Paul Lewis (1984-2002) and Simon Withington (2003-2006).