The exact provenance of the series of 'subject files' found for each LMS/CCWM region is unclear, i.e. whether the organisation of files by subject is contemporary, or whether the files were put together at a later date to create 'artificial' series for greater ease of reference. Brief references found in descriptions of the historical organisation of the archive suggest that a new series of 'subject files' was introduced in 1936, which ran concurrently with missionary personal files, with some initial overlap in content. The files contain the correspondence and supporting papers of the Foreign Secretary for that region, suggesting that the creation and organisation of the files was originally theirs.
Subject files cover a broad spectrum of issues. Across all regions they include correspondence and papers relating to Secretarial Visits or Deputations; minutes and papers of district committees, missionaries' committees, mission councils and bodies representing different stages in the development of independent indigenous churches, and the transition of authority from the LMS/CCWM; papers relating to particular people, places or issues, such as theological education, teacher training, youth movements such as the Boys' Brigade, printing presses, land ownership and other legal matters, local situations arising from the Second World War (1941-1950 accrual) and its aftermath, initiatives and programmes such as the New Advance, local anniversaries and jubliee celebrations, relations with other missionary societies and organisations, natural disasters and relief work, and some publications.