Israeli West Bank barrier in the context of Qalandia Camp

A border barrier, border fence or border wall is a separation barrier that runs along or near an international border. Such barriers are typically constructed for border control purposes such as curbing illegal immigration, human trafficking, and smuggling. Some such barriers are constructed for defence or security reasons. In cases of a disputed or unclear border, erecting a barrier can serve as a de facto unilateral consolidation of a territorial claim that can supersede formal delimitation. A border barrier does not usually indicate the location of the actual border, and is usually constructed unilaterally by a country, without the agreement or cooperation of the other country.

Examples of border walls include the ancient Great Wall of China, a series of walls separating China from nomadic empires to the north. The construction of border barriers increased in the early 2000s; half of all the border barriers built since World War II, which ended in 1945, were built after 2000.

Israeli settlements, also called Israeli colonies, are the civilian communities built by Israel throughout the Israeli-occupied territories. They are populated by Israeli citizens, almost exclusively of Jewish identity or ethnicity, and have been constructed on lands that Israel has militarily occupied since the Six-Day War in 1967. The international community considers Israeli settlements to be illegal under international law, but Israel disputes this. In 2024, the International Court of Justice (ICJ) found in an advisory opinion that Israel's occupation was illegal and ruled that Israel had "an obligation to cease immediately all new settlement activities and to evacuate all settlers" from the occupied territories. The expansion of settlements often involves the confiscation of Palestinian land and resources, leading to displacement of Palestinian communities and creating a source of tension and conflict. Settlements are often protected by the Israeli military and are frequently flashpoints for violence against Palestinians. Furthermore, the presence of settlements and Jewish-only bypass roads creates a fragmented Palestinian territory, seriously hindering economic development and freedom of movement for Palestinians.

As of April 2025, Israeli settlements exist in the West Bank (including East Jerusalem), which is claimed by the Palestine Liberation Organization (PLO) as the sovereign territory of the State of Palestine, and in the Golan Heights, which is internationally recognized as a part of the sovereign territory of Syria. Through the Jerusalem Law and the Golan Heights Law, Israel effectively annexed both territories, though the international community has rejected any change to their status as occupied territory. Although Israel's West Bank settlements have been built on territory administered under military rule rather than civil law, Israeli civil law is "pipelined" into the settlements, such that Israeli citizens living there are treated similarly to those living in Israel. Many consider it to be a major obstacle to the Israeli–Palestinian peace process. In Legal Consequences of the Construction of a Wall in the Occupied Palestinian Territory (2004), the ICJ found that Israel's settlements and the then-nascent Israeli West Bank barrier were both in violation of international law; part of the latter has been constructed within the West Bank, as opposed to being entirely on Israel's side of the Green Line.

The Legal Consequences of the Construction of a Wall in the Occupied Palestinian Territory (commonly known as the Israeli Wall advisory opinion) of 9 July 2004 is an advisory opinion issued by the International Court of Justice (ICJ) in relation to the Israeli West Bank barrier.

Legal Consequences arising from the Policies and Practices of Israel in the Occupied Palestinian Territory, including East Jerusalem, was a proceeding before the International Court of Justice (ICJ), the highest legal body of the United Nations (UN), stemming from a resolution adopted by the United Nations General Assembly (UNGA) in December 2022 requesting the Court to render an advisory opinion relating to the legality of the Israeli occupation of the Palestinian territories.

Israel has occupied the Palestinian territories, which comprise the West Bank (including East Jerusalem) and the Gaza Strip, since 1967, making it the longest military occupation in modern history. In 2004, the ICJ delivered an advisory opinion on the Israeli West Bank barrier, deciding that it contravened international law and should be removed. In January 2023, the ICJ acknowledged the UNGA's request for an advisory opinion on the legal consequences arising from Israel's policies and practices in the occupied Palestinian territories.

Israeli apartheid is a system of institutionalized segregation and discrimination in the Israeli-occupied Palestinian territories and to a lesser extent in Israel proper. This system is characterized by near-total physical separation between the Palestinian and the Israeli settler population of the West Bank, as well as the judicial separation that governs both communities, which discriminates against the Palestinians in a wide range of ways. Israel also discriminates against Palestinian refugees in the diaspora and against its own Palestinian citizens.

Since the 1948 Palestine war, Israel has denied Palestinian refugees who were expelled or fled from what became its territory the right of return and right to their lost properties. Israel has been occupying the West Bank and the Gaza Strip since the 1967 Six-Day War, which is now the longest military occupation in modern history, and, in contravention of international law, has been constructing large settlements there that separate Palestinian communities from one another and prevent the establishment of a Palestinian state. The settlements are mostly encircled by the Israeli West Bank barrier, which intentionally separates the Israeli and Palestinian populations, a policy called Hafrada. Jewish Israeli settlers are subject to Israeli civil law, but the Palestinian population is subject to military law. Settlers also have access to separate roads and exploit the region's natural resources at the expense of its Palestinian inhabitants.