With a view to properly framing the functioning and specific features of the collective complaints procedure as an instrument for the protection of social rights, it is necessary to give a brief overview of the treaty system within which it takes places, that is to say the European Social Charter (ESC) – a complex and articulated system, which has changed substantially over time.

As a Council of Europe treaty, the ESC was originally signed in 1961 and was, at that time, the second-born daughter in the family of human rights treaties adopted within the Council of Europe, after its elder sister, the European Convention on Human Rights (ECHR). Just like the ECHR, the Social Charter arose from the decision of the Council of Europe to adopt a treaty to give binding force to the rights enshrined in the Universal Declaration of Human Rights, adopted by the United Nations in December 1948. In fact, as has been the case at the UN level for the two international covenants on human rights, the Council of Europe member states also opted for adopting two separate treaties: one on civil and political rights, which was the 1950 ECHR, and the other relating to social and economic rights, namely, the ESC, which was adopted 11 years later.

Although it had been in force since the mid-1960s, for a long time the Charter was a somewhat obscure and virtually ineffective instrument. It was not until the end of the 1980s and the beginning of the 1990s, at the end of the Cold War, that the Council of Europe decided to relaunch the ESC. The idea was both to make the Charter effective by aligning it as closely as possible with the ECHR and to modernise it, by adding new rights, in order to properly take into consideration the individual and collective social needs which were emerging in a changed world. One could also say that, by virtue of the institutional reforms started in those years, the Council of Europe has intended to give a substantial and effective meaning to the principle that human rights are indivisible and that social rights are human rights on an equal footing with civil and political rights.