Seguro Popular (Sistema de Protección Social en Salud)
Systemic health-financing innovation created by law in 2003 under health secretary Julio Frenk, which extended public insurance to the population without social security: more than 53 million people enrolled in its first decade, with coverage declared universal in 2012.
illustrative atlas image · Alena Shekhovtcova / Pexels01 The context
It financed explicit packages of services and a fund for catastrophic-cost illnesses. It was extensively evaluated (including a randomized evaluation published in The Lancet) and cancelled by the federal government: it closed in January 2020 and was replaced by INSABI, which in turn disappeared in 2023.
02 How it works
03 What it stands on
The evidence 3 ›
04 Lessons learned
Three documented lessons (McDonald, Touchton, Knaul, Arreola-Ornelas and Frenk 2023; Lancet 2023 and 2025): (1) a reform without institutional safeguards does not survive political polarization: it was dismantled in 2019-2020 after being branded corrupt, with no functional replacement and on the eve of a pandemic; (2) the abrupt withdrawal collapsed high-cost care for the uninsured: drops of 80.7% in acute myocardial infarction, 78.4% in neonatal intensive care and 74.5% in childhood cancer between 2018 and 2021, with an increase in catastrophic out-of-pocket spending; (3) insufficient financing (Mexico spent 5.4% of GDP on health vs 7.4% regionally) and system fragmentation left the reform vulnerable. The case teaches at once how to build a universal coverage reform and how not to undo one.