The play is based on an unofficial strike amongst female textile workers in Leeds in February 1970, demanding equal pay with male workers. Dramatist Colin Welland's mother-in-law was involved in the strike, and Welland interviewed many of those involved while preparing his script. This was the first strike by the textile workers in Leeds in 36 years. The script was originally written for Granada Television, but they rejected it initially on the grounds that it would be too expensive, although it later emerged that some at Granada were worried that the political radicalism of the play might upset advertisers. Welland then took the script to the BBC, and it was produced for the Play for Today series. After being accepted in May 1972, the play's production was continuously held up by concerns about defamation, made particularly acute by filming in Leeds, and some aspects of the play were changed to obscure the identities of the employers in the 1970 strike. (thetvdb.com)