This sub-series consists of correspondence between BOCSPA and the spinning companies and the local employers' associations, especially the Bolton Master Cotton Spinners Association (BMCSA). After the First World War the BMCSA usually dealt directly with the Association about disputes at particular firms.
The correspondence deals with a panoply of industrial relations issues, including wages and wage lists, working conditions, disciplinary matters, health and safety, `bad spinning' and `fine wrapping' disputes, and strikes and lockouts.
From c. 1930 the correspondence also includes copies of the Association's replies, thereby duplicating much of the material found in BCS1/5/4. For the years 1961-1964, some employers' correspondence is filed in the general correspondence series. The series is an invaluable source of information about the application of wage lists in practice, working conditions in the mule rooms, relationships between employers and unions, and relationships within the mill, including those within the spinning team.