On 6^th June 1951, the International Labour Organisation (which had been founded in 1919) adopted the Equal Pay Convention (number 100), which stated that:

“the term equal remuneration for men and women workers for work of equal value refers to rates of remuneration established without discrimination based on sex”.

However, the Convention was unclear about what equal pay for work of equal value legally means. Additionally, states were not obliged to introduce actual legislation to ratify the Convention, they could also choose to leave it up to the social partners to implement, namely, the trade union bodies (usually the LO, the national confederation of trade unions in each of the Scandinavian countries), and the organisations for the employers (usually the respective national confederations of employers.

The parliaments of Norway, Sweden, and Denmark went on to debate whether they should ratify the Convention and how equal pay should be implemented. The main difficulty with implementing the Convention by passing an equal pay law was that wages in the private sector in all three countries were determined through the collective bargaining system. This system consisted – and still does – of the workers’ and employers' organisations being responsible for bargaining wages and working conditions, with parliament only intervening if absolutely necessary. The Scandinavian countries also each have a system of separate and independent institutions for handling and settling disputes over collective bargaining agreements. Passing an equal pay law would dilute this self-governing labour market.

An extra layer of pressure to implement the convention came in 1957 when the European Economic Community (EEC, since 1992 the EU/European Union) decided that a country had to implement the principal of equal pay if it wanted to be a member of the federation. This aspect became particularly relevant for Denmark which was keener to join Europe and was the first Nordic country to do so in 1973.

Given the imprecise wording of the Convention, there were mixed opinions on how it was to be ratified. Norway and Denmark took the view – at least initially – that the Convention did not require parliament to pass an actual law, whereas Sweden thought a law was likely to be necessary. In fact, it was Norway that became the first Scandinavian country to ratify the ILO Equal Remediation Convention in 1959 (after Iceland in 1958), and Denmark followed suit in 1960. Sweden initially took the view that they did not want to interfere with the Nordic model of wage bargaining, but there was mounting pressure to pass legislation in the wake of the other Nordic countries doing so. In the end, the social partners in Sweden agreed to remove the gendered wage disparity of their own accord in 1960 as they predicted that the government would take action sooner rather than later – which they did, choosing to ratify the Convention in 1962.

Removing the gendered wage system in the private sector could not happen instantaneously, however, and in both Norway and Sweden, it was decided that it would be replaced with gender-neutral pay rates over the course of five years. It was the beginning of heated discussions that continue today: How do we objectively measure work of equal value? For the purposes of this article, it is suffice to say that the three Scandinavian countries initially took different approaches. In Norway and Denmark, neutral job evaluations would rank occupations based on their value were attempted with very mixed results. Despite requests from Swedish women, Sweden was to remove the gendered wages without any new job evaluations. Throughout these attempts, many women feared that women-dominated occupations would continue to be ranked of lower value – and therefore attract a lower wage – than men's. So, while the attempts to try to accurately implement the Convention must be lauded, historian Yvonne Hirdman has, for example, claimed that the Swedish arrangement generated little enthusiasm among women at the time.