The International Labour Organisation (ILO) adopted Convention 100 on Equal Remuneration between men and women on the 29 June 1951.

The Convention includes the principle of equal value, and Article 3 requires that ‘measures shall be taken to promote objective appraisal of jobs on the basis of the work to be performed’.

Although the UK is a founder member of the ILO, which was established under the Treaty of Versailles in 1919 following the end of the First World War, it did not ratify Convention 100 until 15 June 1971 and did not implement equal pay for work of equal value until 1983.