The OPERA Framework ‘should take concrete, deliberate and targeted measures’ to eliminate discrimination.14 However, this duty does not prevent differential treatment where this is necessary to eliminate historical injustices (known as positive discrimination or affirmative action), as the duty of non-discrimination requires eliminating both formal and substantive discrimination.15 Numerous national courts and regional and international adjudicatory bodies have made decisions related to ESC rights on the grounds of non-discrimination and equal treatment and some have interpreted non-discrimination expansively to include situations where a combination of factors resulted in discriminatory circumstances or disproportionally affected particular social groups.16 The ‘minimum core obligations’ of each of the rights enshrined in the Covenant impose, in the Committee’s view, a duty on states ‘to ensure the satisfaction of, at the very least, minimum essential levels of each of the rights’ regardless of their level of economic development.17 Failure by the state to meet these minimum levels would lead to a prima facie presumption that it has violated the Covenant—a presumption that can only be discharged if the state can demonstrate that ‘every effort has been made to use all resources that are at its disposition in an effort to satisfy, as a matter of priority, those minimum obligations’. Over the past two decades, the Committee has adopted a number of General Comments which further define the minimum core of Covenant rights such as the right to food, water, health, housing, and education.18 Finding consensus on the content of the minimum core concept and its application to specific states has proved difficult.19 Courts in some countries, such as South Africa, have rejected the concept, though others, such as Germany and Switzerland, have used it to translate constitutional principles of human dignity into positive state obligations.20 Despite its imprecision, the appeal of the minimum core concept lies in its insistence that states must give first priority to fulfilling a basic minimum of ESC rights, universally, for all those within its jurisdiction, over and above all other policy and economic objectives, thus creating a higher burden of proof on states to demonstrate they are using the maximum of their available resources to achieve these outcomes. Looking ahead, concepts from other fields may increasingly enrich the definition of the minimum core. For example, the ‘Social Protection Floor Initiative’ (SPF Initiative), adopted in 2009 as one of the UN’s nine key strategies to cope with the global financial crisis, mandates national task forces to develop definitions of the social protection floor, which may be relevant in further defining minimum essential levels of ESC rights fulfillment.21 In addition to focusing on immediate obligations, the Committee has dealt with the question of progressive realization by elaborating on the duty to ‘take steps’. In particular, General Comment No. 3 stressed that while the realization of relevant rights, which is an obligation of result—may generally be achieved progressively, the duty to take steps—which is obligation of conduct—is immediate: [W]hile the full realization of the relevant rights may be achieved progressively, steps towards the goal must be taken within a reasonably short time after the Covenant’s entry into force ... Such steps should be deliberate, concrete and targeted as clearly as possible towards meeting the obligations recognized in the Covenant.22 The means used to satisfy the obligation ‘to take steps’ are ‘all appropriate means, including particularly the adoption of legislative measures’.23 The delineation between obligations of conduct and of result will rarely be exact, and the policy-making process is not necessarily linear. Nevertheless, putting emphasis on the steps taken by a state appropriately recognizes that states’ primary obligations should relate to their conduct, which they directly control, in contrast to results, which are often the product of a confluence of many factors.24 4