The pursuit of social justice fundamentally requires gender equality, just as meaningful gender equality necessitates social justice. This means that each is integral to achieving the other. While commonly characterised as "two sides of the same coin," this paper aims to demonstrate they are, in fact, the very coin itself: a unified entity forged into an indissoluble foundation. As perceptions and definitions of social justice in different contexts demonstrate, the term "social justice" remains deceptively simple in everyday usage. Similarly, the term "gender equality" has emerged to bring together a large number of basic precepts crucial to removing sex-based discrimination in all spheres of human endeavour. While social justice arises from binding and non-binding instruments, and workplace social justice stems from the 1919 ILO Constitution and international labour standards, gender equality springs from a plethora of international treaties negotiated by States to end discrimination based on sex. This article examines the content and overlay of these concepts using a comparative law methodology, citing examples where social justice and gender equality combine. It reviews texts that give context to social justice, texts that define gender equality, and the main hard law treaties giving substance to gender equality, providing applied illustrations of implementation of gender equality. The article concludes that without these principles and rights, social justice remains illusory. If decision-makers strive to produce the composite coin itself, the two concepts melded together as a whole will lead to genuine improvements in the quality of all human life, as this paper demonstrates.

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