The umbrella of International Economic Law seems to have broadened to encompass subjects as diverse as trade, finance, investment, development, and intellectual property to name a few. The increasing specialisation of sectors within international economic relations gives rise to questions about the social constitutions underlying the development of International Economic Law. Social constitutions emerge as groups or regimes with the capacity to organise themselves according to their own rationality. These social constitutions may act as counterforces to other constitutional regimes, therefore competing for positions of power and social influence. The impact of social constitutions in the development of International Economic Law raises concerns about the nature of such constitutions and their power, as well as the implications this has for social justice. This article will explore the emergence of social constitutions in International Economic Law through the lens of social constitutionalism. The article argues that the differentiation of society into functionally differentiated subsystems and of International Economic Law into highly specialised sectors requires addressing the emergence of social constitutions upon the differentiation of power. The article will examine the differentiation of power as a potential construct for resistance, in which social constitutions arise as structural as opposed to spontaneous participants in the construction of International Economic Law. By using Elsig’s facets of power – structural, procedural and ideational, the article sheds light on a more inclusive and just International Economic Law, where social constitutions of resistance emerge as empowered actors in the international economic system.