Collins first became well known for her role as the maid Sarah in the 1970s ITV drama series "Upstairs, Downstairs". The character was in the first two series. In the second series she appeared with her actor husband, John Alderton. In 1979, they starred in a spin-off, "Thomas & Sarah". They also starred in the sitcom "No, Honestly". This was written by Terence Brady and Charlotte Bingham. From 1975 to 1978, they worked together in a series of short-story adaptations called "Wodehouse Playhouse". In 1983, they narrated the animated British children's TV series "Little Miss".