Serbia-Bosnia and Herzegovina: Serbia delimited about half of the boundary with Bosnia and Herzegovina, but sections along the Drina River remain in dispute

Serbia-Bulgaria: none identified

Serbia-Croatia: Serbia and Croatia dispute their border along the Danube; Serbia claims the border is the median between the current Danube shorelines, with the land to the eastern side of the median belonging to Serbia; Croatia contends that the boundary is demarcated according to historic maps, despite the river having meandered since then

Serbia-Hungary: none identified

Serbia-Kosovo: Serbia with several other states protested the US and other states' recognition of Kosovo's declaration of its status as a sovereign and independent state in February 2008; ethnic Serbian municipalities along Kosovo's northern border challenge final status of Kosovo-Serbia boundary; since 1999, NATO-led Kosovo Force peacekeepers under UN Interim Administration Mission in Kosovo (UNMIK) authority have continued to keep the peace within Kosovo between the ethnic Albanian majority and the Serb minority; in October 2021, NATO-led KFOR increased patrols along the border with Serbia to deescalate hostilities caused by a dispute over license plates

Serbia-Montenegro: the former republic boundary serves as the boundary until a line is formally delimited and demarcated

Serbia-North Macedonia: none identified

Serbia-Romania: none identified

Guatemala-Belize: demarcated but disputed boundary due to Guatemala’s claims to more than half of Belizean territory; line of Adjacency operates in lieu of an international boundary to control influx of Guatemalan squatters onto Belizean territory; smuggling, narcotics trafficking, and human trafficking are also problems; the dispute was referred to the ICJ in 2019 for binding resolution; the 12-nm territorial sea claims of Belize and Honduras close off Guatemalan access to Caribbean in the Bahia de Amatique; maritime boundary remains unresolved pending further negotiation

Guatemala-Mexico: thousands of impoverished Guatemalans and other Central Americans cross the porous border with Mexico looking for work in Mexico and the US

Nicaragua-El Salvador-Honduras: the 1992 ICJ ruling for El Salvador and Honduras advised a tripartite resolution to establish a maritime boundary in the Gulf of Fonseca, which considers Honduran access to the Pacific; the court ruled, rather, that the Gulf of Fonseca represents a condominium, with control being shared by El Salvador, Honduras, and Nicaragua; the decision allowed for the possibility that the three nations could divide the waters at a later date if they wished to do so

Nicaragua-Costa Rica: Nicaragua and Costa Rica regularly file border dispute cases with the ICJ over the delimitations of the San Juan River and the northern tip of Calero Island, virtually uninhabited areas claimed by both countries; there is an ongoing case in the ICJ to determine Pacific and Atlantic ocean maritime borders as well as land borders; in 2009, the ICJ ruled that Costa Rican vessels carrying out police activities could not use the river, but official Costa Rican vessels providing essential services to riverside inhabitants and Costa Rican tourists could travel freely on the river; in 2011, the ICJ provisionally ruled that both countries must remove personnel from the disputed area; in 2013, the ICJ rejected Nicaragua's 2012 suit to halt Costa Rica's construction of a highway paralleling the river on the grounds of irreparable environmental damage; in 2013, the ICJ, regarding the disputed territory, ordered that Nicaragua should refrain from dredging or canal construction and refill and repair damage caused by trenches connecting the river to the Caribbean and upheld its 2010 ruling that Nicaragua must remove all personnel; in early 2014, Costa Rica brought Nicaragua to the ICJ over offshore oil concessions in the disputed region; in 2018, the ICJ ruled that Nicaragua must remove a military base from a contested coastal area near the San Juan River, and that Costa Rica had sovereignty over the northern part of Isla Portillos, including the coast, but excluding Harbour Head Lagoon; additionally, Honduras was required to pay reparations for environmental damage to part of the wetlands at the mouth of the San Juan River

Nicaragua-Colombia: Nicaragua filed a case with the International Court of Justice (ICJ) against Colombia in 2013 over the delimitation of the Continental shelf beyond the 200 nautical miles from the Nicaraguan coast, as well as over the alleged violation by Colombia of Nicaraguan maritime space in the Caribbean Sea, which contains rich oil and fish resources; as of September 2021, Colombia refuses to abide by the ICJ ruling

Nicaragua-Honduras: none identified