Disputes - international:
abundant rainfall in recent years along much of the Mexico-US border region has ameliorated periodically strained water-sharing arrangements; the US has intensified security measures to monitor and control legal and illegal personnel, transport, and commodities across its border with Mexico; Mexico must deal with thousands of impoverished Guatemalans and other Central Americans who cross the porous border looking for work in Mexico and the US; Belize and Mexico are working to solve minor border demarcation discrepancies arising from inaccuracies in the 1898 border treaty

Refugees and internally displaced persons:
refugees (country of origin): 5,155 (El Salvador) (2018); 64,053 (Venezuela) (economic and political crisis; includes Venezuelans who have claimed asylum or have received alternative legal stay) (2019)
IDPs: 338,000 (government's quashing of Zapatista uprising in 1994 in eastern Chiapas Region; drug cartel violence and government's military response since 2007; violence between and within indigenous groups) (2018)
stateless persons: 13 (2018)

Illicit drugs:
major drug-producing and transit nation; Mexico is estimated to be the world's third largest producer of opium with poppy cultivation in 2015 estimated to be 28,000 hectares yielding a potential production of 475 metric tons of raw opium; government conducts the largest independent illicit-crop eradication program in the world; continues as the primary transshipment country for US-bound cocaine from South America, with an estimated 95% of annual cocaine movements toward the US stopping in Mexico; major drug syndicates control the majority of drug trafficking throughout the country; producer and distributor of ecstasy; significant money-laundering center; major supplier of heroin and largest foreign supplier of marijuana and methamphetamine to the US market