There were many skeptics when Mexico announced plans to open its oil and gas sector for foreign investment a few years ago—and for good reason. After more than 70 years of a state monopoly, the country would have to change its constitution to allow international companies to develop Mexico’s hydrocarbon reserves.

But five years ago, President Enrique Peña Nieto presented his proposed constitutional reform to the Mexican Congress, and in a matter of four months, his plan was approved by the Senate and the Chamber of Representatives. On Dec. 18, 2013, Mexico declared the reform constitutional.

This was a major first step, but there was enormous work to be done before the country could begin to develop its nearly 10.5 Bbbl of proved oil reserves and approximately 489.8 Bcm (17.3 Tcf) of proved natural gas. Mexico had neither the experience nor the technology to develop its reserves; it would have to create a regulatory regime that would entice international investment and bring in the necessary expertise.

The success that has been achieved since the constitutional reform is impressive. In a report published in May, analysts at Wood Mackenzie explained how Mexico’s competitive fiscal terms have borne fruit, noting that eight licensing rounds have resulted in the award of 83 blocks, among these some of the highest profile tenders in the world in the last two years. According to the report, the country achieved a licensing award success of 70% in 2017, which is twice the global average.

Official fourth-quarter 2017 results reported by state oil company Petróleos Mexicanos (Pemex) further illustrate Mexico’s successes, highlighting significant milestones that year that included a farm-out on the Trion Field to BHP Billiton and the award of deepwater Block 3 North to a consortium formed by Pemex, Chevron and Inpex. In the fourth quarter alone, Pemex recorded its first onshore farm-outs (for the Ogarrio and Cárdenas-Mora fields) and the largest onshore discovery of the last 15 years at Ixachi.

Pemex believes it will reach first production at Ixachi in 2020 and has identified an additional seven “clusters” that it will focus on in the near term: Juspí, Bedel-Gasifero, Cinco Presidentes, Giraldas-Sunuapa, Bacal-Nelash, Artesa and Lacamango. The company is seeking international partners in the hope of fast-tracking development.

The search for partners, in fact, was one of the company’s primary goals in May at the Offshore Technology Conference (OTC) in Houston. At the conference, Pemex CEO Carlos Treviño Medina announced the company is looking to form strategic partnerships with other leading companies in the global oil sector to expedite the internationalization process. According to an official company statement, Treviño Medina met with senior managers of leading oil companies at OTC to share details about the seven blocks targeted for development.

Companies that have taken steps to get into the Mexican market are hoping the presidential election does not change what is at present a rosy picture. A serious contender for the presidency, Andres Manuel Lopez Obrador of the National Regeneration Movement, Movimiento Regeneración Nacional (aka MORENA) party, has openly opposed energy reforms and if elected, is likely to rein in development, possibly cutting back the acreage offered and slowing the permitting process.

The progress made to date is impressive, and Pemex has shown it is serious about making foreign players welcome. It would be unfortunate if a change in administration at the presidential level were to compromise what the Peña Nieto regime worked so hard to achieve.