A/69/302 reasonable justification for a difference of treatment, “unless every effort has been made to use all resources that are at the State party’s disposition in an effort to address and eliminate the discrimination, as a matter of priority”. International human rights law includes several widely agreed commitments to equality and a set of tools and mechanisms by which to achieve it, including the requirement that duty bearers address the root causes of inequality and discrimination. 40. There is now growing consensus among States that the post -2015 agenda must include tackling the reduction of inequalities. The new development framework must be articulated in a manner that not only does not accept or accommodate inequalities and disparities, but also actively seeks to tackle them. Equality, however, does not mean treating all cases in the same way, given that doing so would reduce it to formal equality. Substantial equality means treating differently persons who are in a different situation. It refers to bringing all persons to a level playing field and progressively working to improve the quality and levels of service accessible to marginalized groups that are usually left behind, including migrants. 41. The Special Rapporteur strongly recommends that the post-2015 agenda incorporate equality, which in itself is a fundamental human rights principle, as a stand-alone and cross-cutting goal, aiming to progressively eliminate disparities within and between marginalized groups, including migrants, and the general population, as well as between countries, to achieve more inclusive forms of development. 42. Incorporating the equality principle will create incentives to end discrimination and adopt affirmative-action measures or temporary special measures where barriers exist and persist. In addition, it will require States to look beyond average attainments and adopt more effective ways of collecting disaggregated data on inequality affecting marginalized groups, in order to allow for disparate impacts to be identified. Specific measurements will be required to assess the extent to which migrants benefit from the post-2015 framework. 43. A goal on equality should be broad, not only focusing on income disparities, but also identifying key dimensions of economic and social inequality, including in terms of participation and access to essential services such as health, education and social protection. This should be framed with reference to the civil, political, economic, social and cultural rights of all. In addition, targets and indicators relating to employment and fiscal or redistributive policies must be included under this goal and structural determinants of inequality should also be addressed. 44. Equality should be cross-cutting. All new targets must mainstream equality and explicitly focus on reducing inequalities, in order to measure and tackle unequal enjoyment of the opportunities and benefits of progress across different areas. Targets and indicators must focus on the situation of the most marginalized, whose rights and needs should be considered and accorded priority. As such, success should be measured by the progress made by all, including the most marginalized groups, including migrants, rather than only by overall progress. Targets and indicators 45. Targets under equality should focus on the empowerment and inclusion of groups that are often marginalized, including migrants, and include a commitment to 10/26 14-59006