BackgroundAlmost seven years after the publication of the final report of the World Health Organization’s Commission on Social Determinants of Health (CSDH), its third recommendation has not been attended to properly. Measuring health inequities (HI) within countries and globally, in order to develop and evaluate evidence-based policies and actions aimed at the social determinants of health (SDH), is still a pending task in most low and middle income countries (LMIC) in the Latin American region. In this paper we discuss methodological and conceptual issues to measure HI in LMIC and suggest a three-stage methodology for the creation of observatories on health inequities (OHI) and social determinants of health, based on the experience of the Brazilian Observatory on Health Inequities (BOHI) that has been successfully operating since 2010 at the Fundação Oswaldo Cruz (FIOCRUZ).MethodsA three-stage methodology for the creation of an OHI was developed based on a literature review on the following topics: SDH, HI measurement, and the process of setting-up of health observatories; followed by semi-structured interviews with key informants from the BOHI. We describe the three stages and discuss the replicability of this methodology in other Latin American countries. We also carried out a search of suitable national information systems to feed an OHI in Mexico, along with an outline of the institutional infrastructure to sustain it.ResultsWhen implementing the methodology for an OHI in LMIC such as Mexico, we found that having strong infrastructure of information systems for measuring HI is required, but not sufficient to build an OHI. Adequate funding and intersectoral network collaborations lead by a group of experts is a requirement for the consolidation and sustainability of an OHI in LMIC.ConclusionAccording to the described methodology, and the available information systems on health, the creation of an OHI in LMIC, particularly in Mexico, is plausible in the near future. However, institutional support (in academic, financial, and policymaking terms) is essential to materialize such needed instance, thus locally contributing to attain health equity.