An internally displaced person, or IDP, is someone who has been forced to leave their home but has not crossed an international border. That single geographic fact, whether or not someone made it to another country, determines almost everything about the legal protections available to them. Despite facing many of the same threats as refugees, IDPs remain under the authority of their own government, and international law treats them very differently as a result. Tens of millions of people worldwide fit this description at any given time, making internal displacement one of the largest and least understood humanitarian crises on the planet.
What Makes Someone an IDP Rather Than a Refugee
The distinction sounds simple: refugees cross borders, IDPs do not. But the consequences are enormous. Under international law, refugees are entitled to systematic protection and assistance through dedicated treaties and institutions, precisely because they have crossed an international frontier. IDPs, despite being compelled to flee their homes by the same kinds of violence, persecution, or disaster, lack that explicit, dedicated legal protection in international law.1Journal of Refugee Studies. Internally Displaced Persons and Refugees: Toward a Legal Synthesis? They remain, legally speaking, citizens of their own country, and their government bears primary responsibility for their welfare. When that government is the cause of their displacement, or is too weak or unwilling to help, IDPs can find themselves in a kind of protection vacuum.
The concept of sovereignty sits at the center of this gap. Because IDPs have not left their country, other nations and international organizations face political and legal barriers to intervening on their behalf. Researchers have described IDPs as effectively “trapped by sovereignty,” lacking the same explicit protections that the international refugee system provides to those who managed to cross a border.2World Affairs. TRAPPED BY SOVEREIGNTY The result is that two people fleeing the same conflict may have dramatically different access to aid and legal status depending on whether they ended up on one side of a border or the other.
There is no global binding treaty specifically for IDPs equivalent to the 1951 Refugee Convention. What does exist is the UN Guiding Principles on Internal Displacement, adopted in 1998, which outlines the rights and protections IDPs should receive. These principles are influential but not legally binding. The most significant binding law is regional: the African Union’s Kampala Convention, adopted in 2009, which creates obligations for African states to protect and assist IDPs. It has been ratified by nearly two-thirds of African Union member states, making it the strongest legal instrument specifically addressing internal displacement anywhere in the world.3Refugee Survey Quarterly. The Protection and Assistance of Internally Displaced Persons under the Kampala Convention: An Institutional Approach Outside Africa, most IDP protections depend on general human rights law and the goodwill of national governments.
Why People Become Internally Displaced
Armed conflict is the most visible driver. Civil wars, insurgencies, ethnic violence, and military operations uproot millions of people who flee to safer areas within their own country. Colombia’s decades-long armed conflict offers one of the starkest examples: forced migration there has been classified as an intentional, human-generated disaster involving massive population displacement that escalated into a protracted humanitarian crisis.4PubMed Central. Internally Displaced “Victims of Armed Conflict” in Colombia: The Trajectory and Trauma Signature of Forced Migration Nigeria, Syria, the Democratic Republic of Congo, Sudan, and Ukraine are among the many other countries where conflict has created enormous IDP populations.
But conflict is not the only cause. Natural disasters, including floods, earthquakes, hurricanes, and droughts, displace millions each year, sometimes more than conflict does in a given year. Climate change is intensifying this pattern by making extreme weather events more frequent and severe. Development projects such as dams, highways, and mining operations also uproot communities, though these cases receive far less international attention. And some displacement is driven by communal violence, such as clashes between farming and herding communities over land and water, which may not rise to the level of what most people picture as “armed conflict” but is devastating for the people caught in it.
Where IDPs End Up Living
The popular image of displacement is a tent camp in a remote area, and camps certainly exist. But the reality is that the majority of IDPs move to urban centers rather than formal camps. They settle in cities and towns, often blending into existing neighborhoods or moving into informal settlements on the outskirts. This creates challenges that camp-focused humanitarian responses were not designed to address.5Refugee Survey Quarterly. When Internal Displacement Meets Urbanisation: Making Cities Work for Internally Displaced People
When IDPs arrive in urban informal settlements, they face a particular set of problems. Housing is precarious, with people living in structures that may not have been designed for habitation. Services like clean water, sanitation, electricity, and healthcare are already under pressure in these areas before displacement adds to the population. Transitional shelter programs sometimes struggle to fit the urban informal context, where land tenure is ambiguous and building codes may not apply in practice.6Disaster Prevention and Management: An International Journal. Fit for purpose? Lessons from transitional shelter provision for internally displaced persons in urban informal settlements in Brazil The sheer mismatch between how humanitarian aid is typically organized, around camps and visible clusters, and where IDPs actually live makes it harder to reach them with assistance.
Because internal displacement is often protracted, lasting years or even decades, these “temporary” living situations become permanent by default. People build social networks, find informal work, and enroll their children in local schools, but they do so without secure housing, without formal recognition of their presence, and without the safety nets available to established residents.
The Physical Health Toll
Displacement makes people sick in predictable ways. A scoping review of the health literature found that the leading causes of death among IDPs are preventable infectious diseases: diarrhea, malaria, and respiratory illnesses. These are driven by overcrowding, unsanitary and substandard living conditions, limited access to healthcare, and malnutrition.7PubMed Central. Understanding the health needs of internally displaced persons: A scoping review In other words, IDPs are dying not from exotic diseases but from conditions that are entirely treatable if basic services are available. The gap between what kills IDPs and what modern medicine can handle is the clearest indictment of the protection gap they face.
Chronic diseases, maternal health complications, and child malnutrition compound these problems, especially in long-term displacement. Healthcare infrastructure in the areas where IDPs settle is often already strained. Displacement can also sever people from whatever healthcare access they previously had, including ongoing treatments for conditions like HIV, tuberculosis, or diabetes. Children and the elderly are disproportionately vulnerable, as they are in most humanitarian crises, but the lack of systematic tracking of IDP health outcomes means the full picture is hard to quantify.
Mental Health in Displacement
The mental health consequences of internal displacement are severe and well-documented. A meta-analysis published in BMJ Global Health found that roughly four in ten IDPs met criteria for post-traumatic stress disorder, with a pooled prevalence of about 40%. Depression affected about 36%, generalized anxiety disorder about 29%, and insomnia roughly 39%. Compared to non-displaced populations, IDPs had 70 to 117 percent higher odds of PTSD and depression.8BMJ. Mental health of internally displaced persons: a meta-analysis These are staggeringly high rates. For context, the general population prevalence of PTSD in most countries is in the low single digits.
Studies focused on specific displacement contexts paint an even grimmer picture. In northern Uganda, where conflict with the Lord’s Resistance Army forced hundreds of thousands into camps, over half of respondents met symptom criteria for PTSD and about two-thirds met criteria for depression.9PubMed Central. Factors associated with post-traumatic stress disorder and depression amongst internally displaced persons in northern Uganda A systematic review focused specifically on Africa found a pooled PTSD prevalence of about 51% among IDPs, with several factors strongly associated with higher risk: being female, being unemployed, having experienced multiple traumatic events, lacking medical care during illness, and having been displaced more than once. People who had experienced twelve or more traumatic events had more than five times the odds of developing PTSD compared to those with fewer exposures.10PLOS ONE. Post-traumatic stress disorder and associated factors among internally displaced persons in Africa: A systematic review and meta-analysis
Repeated displacement deserves emphasis as a risk factor. Many IDPs are not uprooted just once. They may flee an initial crisis, attempt to return, and be displaced again by renewed violence or instability. Each cycle of displacement compounds the psychological damage. The accumulation of traumatic exposures, loss of social networks, and erosion of any sense of stability creates conditions where mental illness becomes the norm rather than the exception.
Gender-Based Violence Against Displaced Women
Women and girls face specific dangers during displacement that go far beyond the general risks. Gender-based violence, including physical assault, sexual violence, forced marriage, and threats of harm, is pervasive in IDP settings. The evidence from multiple countries is consistent on this point, even though exact rates vary by context.
In central Ethiopia, a mixed-methods study found that about 31% of internally displaced women had experienced gender-based violence, with roughly a quarter reporting incidents in the past year. The most common forms were threats of violence, physical violence, forced marriage, and sexual violence. Nearly 80% of these incidents occurred within IDP camps, and the perpetrators were most often intimate partners or family members.11PubMed Central. Investigating Gender-based violence against internally displaced women in Debre Berhan, Central Ethiopia: A mixed-methods study using the socio-ecological framework A separate study in Northwest Ethiopia found a one-year prevalence of about 38%, with young women aged 18 to 24 facing roughly three and a half times the odds of violence compared to older women. Lacking social protection networks tripled the risk.12PubMed Central. Gender-based violence and its associated factors among internally displaced women in Northwest Ethiopia: a cross-sectional study
In southern Nigeria, a study of 300 displaced women found that about 22% had experienced violence perpetrated by non-family members during conflict, and about 14% experienced post-conflict violence. Physical violence was more common during active conflict, while sexual violence was more common afterward. Adolescents, unmarried women, those who had never attended school, and recently displaced women were the most vulnerable.13PubMed. Experience of Gender-based Violence by Internally Displaced Women in Southern Nigeria: A Cross-sectional Study The pattern across these studies is clear: displacement shatters protective social structures, concentrates vulnerable people in insecure settings, and creates conditions where violence against women flourishes. Reporting remains low, meaning the real prevalence is almost certainly higher than surveys capture.
Economic Shockwaves for Host Communities
Displacement does not only affect the people who are displaced. When large numbers of IDPs arrive in a community, the economic effects ripple outward. A sudden increase in population drives up demand for food, housing, and basic goods, often pushing prices higher. Research on Nigeria, where Boko Haram and other conflicts have caused massive displacement, found that IDP influx negatively affected household-level food security in the communities receiving them.14Elsevier. Armed conflicts, forced displacement and food security in host communities
The economic picture is more nuanced than “displacement is bad for hosts,” though. A review of the economic literature on forced displacement identified two simultaneous shocks that arrive with a displacement crisis. The first is the population shock itself: more people competing for housing, food, and jobs. The second is a public expenditure shock, because international aid, government spending, and humanitarian operations all inject money into the local economy. Aid agencies hire local staff, international workers need local services, and increased consumer demand can create new business opportunities. The net effect depends on the context, but research suggests that the losers are concentrated among low-skilled informal workers who compete directly with displaced people for the same jobs, while the winners tend to be higher-skilled formal workers and business owners who benefit from increased demand.15Journal of Development Economics. The impact of forced displacement on host communities: A review of the empirical literature in economics The people least able to absorb an economic shock are the ones most likely to feel it.
When Displacement Becomes Permanent
The word “displaced” implies something temporary, a disruption that will eventually resolve when people go home. In practice, millions of IDPs live in a permanent state of limbo. Governments may fail to address the root causes of displacement, neglect to create resettlement plans, or ignore the aspirations of displaced people entirely. In Plateau State, Nigeria, a review of decades of displacement found that successive governments had failed to implement the recommendations of commissions set up to address the problem, resulting in continued displacement, unsafe living conditions, and a lack of resettlement plans. Displaced individuals faced prolonged livelihood disruptions, and their preferences for return, reintegration, or resettlement were largely ignored.16Malaysian Journal of Social Sciences and Humanities (MJSSH). A Forgotten Population: Review of Issues and Challenges of Prolonged Displacement in Plateau State, Nigeria
Protracted displacement creates a specific kind of harm. People are not in acute crisis anymore, so they drop off the humanitarian radar. But they have not recovered, either. They may lack formal documentation, making it impossible to access services, own property, vote, or move freely. Their children grow up displaced, sometimes inheriting a liminal status that follows them into adulthood. The international humanitarian system is designed around emergencies, with funding cycles and attention spans that do not easily accommodate situations lasting ten or twenty years. When displacement drags on, the people affected become, as one study put it, a forgotten population.
Can People Actually Go Home
International frameworks describe three “durable solutions” for displacement: return to the place of origin, local integration in the area where people settled, or resettlement elsewhere in the country. Of these, return gets by far the most attention, and peace agreements tend to treat it as the preferred solution. But the reality of return is complicated.
Colombia’s Victims’ Law of 2011 represents one of the most ambitious attempts to facilitate return through land restitution. The law aimed to restore property rights to people who had been dispossessed during the armed conflict, formalize their ownership, and enable them to go back. In practice, researchers found institutional overload, new conflicts arising on the ground as restitution was attempted, and what they described as “unexpected prospects of return,” meaning that the process of giving people their land back was far more complicated and contentious than the law anticipated.17Journal of Human Rights Practice. Ideals and Realities of Restitution: the Colombian Land Restitution Programme
Land restitution faces a deeper structural problem in contexts where property rights are governed by custom rather than formal legal systems. In much of the world, land is held through traditional or communal arrangements rather than title deeds. When conflict displaces people from land held this way, the assumption that they can simply return to their previous rural agricultural livelihoods only holds if the customary land system still functions the way it did before the violence. Research on post-conflict restitution of customary land found that contested authority structures, displaced and returning populations, and contentious land relations make customary land vulnerable to seizure, challenging the assumption that return is always possible.18World Development. Post-conflict restitution of customary land: Guidelines and trajectories of change When the village chief has been killed, when new people have occupied the land, when ethnic balances have shifted, the entire social system that defined who had rights to what may no longer exist.
How Peace Agreements Handle Displacement
You might expect that when warring parties sit down to negotiate an end to conflict, the millions of people displaced by that conflict would be a central concern. The evidence suggests otherwise. A study examining peace agreements from 1992 to 2023 found that fewer than 20% of agreements that addressed internal displacement framed their response in terms of rights, despite international frameworks emphasizing a rights-based approach. Most agreements promoted return as the preferred or default solution, even though international standards stress that IDPs should have the right to choose among return, local integration, or resettlement. And very few agreements addressed IDP participation in decision-making or acknowledged the diverse needs and perspectives of displaced populations.19Refugee Survey Quarterly. Addressing Internal Displacement in Peace Agreements, 1992–2023: Global Trends and Implications
This disconnect matters because peace agreements shape the post-conflict environment. If an agreement treats IDPs as a problem to be solved through return rather than as rights-holders with agency and choices, the resulting policies will push people back toward places that may not be safe, may not offer livelihoods, and may not be where the displaced person wants to go after years of building a life elsewhere. The gap between what international norms say IDPs deserve and what peace processes actually deliver for them remains wide.
The Counting Problem
One underappreciated challenge in the IDP space is simply knowing how many people are displaced and where they are. Refugees are typically registered by UNHCR or host-country authorities when they cross a border. IDPs, by contrast, may never come into contact with any registration system. They move within their own country, often to cities where they blend into existing populations. They may avoid registering because they fear the government that displaced them, or because no registration mechanism exists. Humanitarian organizations have recognized that their methods for estimating IDP populations need significant improvement, both in how data is collected in the field and in the analytical approaches used to generate numbers.20PubMed Central. What we do know (and could know) about estimating population sizes of internally displaced people.
The practical consequence of bad data is bad policy. If you do not know how many IDPs are in a city, you cannot plan health services, school capacity, or water infrastructure for them. If you cannot track when displacement ends, because someone found stable housing and employment and considers themselves no longer displaced, you cannot distinguish protracted displacement from resolved displacement. The global figure of tens of millions of IDPs that organizations cite each year is itself a rough estimate, built from imperfect national counts, satellite imagery, surveys, and modeling. For a crisis of this scale, the uncertainty is striking.
Why Exclusion Clauses Do Not Apply to IDPs
In refugee law, there are exclusion clauses: provisions that deny refugee status to people who have committed war crimes, serious crimes, or acts contrary to the purposes of the United Nations. Some observers have asked whether similar exclusion logic should apply to IDPs, particularly in contexts where combatants and civilians are intermixed among displaced populations. Legal scholarship argues that the concept does not transfer. Being recognized as an IDP does not confer a special legal status the way refugee recognition does, so there is no status to be excluded from. And unlike refugee protection, IDP rights are grounded in international humanitarian law and human rights law, neither of which contains exclusion clauses.21International Journal of Refugee Law. Internally Displaced Persons and Exclusion Clauses Falling within the IDP description does not shield anyone from criminal prosecution, so the rationale for exclusion that exists in refugee law simply does not apply. The distinction is worth understanding because it highlights something important about IDPs: they are not a category of people receiving special privileges. They are people in need whose rights already exist under general law but are routinely unfulfilled.