The System of Social Protection in Health also sought to inject new resources into the health system, and improve resource transfers between federal government and the states. Indeed, public investment in the health system rose from 2.4% to 3.3% GDP between 2003 and 2013. Having operated as a pilot programme between 2001 and 2003, and following reforms to the legal framework underpinning Mexico’s health system, Seguro Popular (SP), was fully launched in January 2004. Some important high-cost interventions remain excluded from the SP package, as discussed in Chapter 3. The significant increase in SP affiliation also represents a significant increase in total population coverage, and an important step towards universal health coverage (UHC).