Vulnerability
What makes people vulnerable?
Vulnerability is the human dimension of disasters: the economic, social, cultural, institutional, political and psychological factors that shape people's lives and environments.
Vulnerability can be a challenging concept to understand because it tends to mean different things to different people. It is often described using a variety of terms including 'predisposition', 'fragility', 'weakness', 'deficiency' or 'lack of capacity'.
Some definitions of vulnerability have included exposure in addition to susceptibility to harm. However, it is now understood that exposure is separate to the 'susceptibility' element of vulnerability, since it is possible to be exposed whilst at the same time not susceptible to natural hazards.
Despite some divergence over its meaning, most experts agree that understanding vulnerability requires more than analysing the direct impacts of a hazard. It also concerns the wider environmental and social conditions that limit people and communities to cope with the impact of hazards.
Components of risk
Disaster risk is the product of hazard, exposure and vulnerability. Hover any element to see what it means, or click to open its reference page.
Adapted from Components of risk on PreventionWeb.
Vulnerability defined
The characteristics determined by physical, social, economic and environmental factors or processes which increase the susceptibility of an individual, a community, assets or systems to the impacts of hazards.
Vulnerability is not simply about poverty, but extensive research over the past 30 years has revealed that it is generally the poor who tend to suffer worst from disasters. Poverty is both a driver and consequence of disaster risk, particularly in countries with weak risk governance, because economic pressures force people to live in unsafe locations (see exposure) and conditions. Susceptibility is often, but not always, associated with certain groups, including women, children, the elderly, the disabled, migrants and displaced populations.
Which factors shape vulnerability?
Five groups of factors – physical, social, informational, economic and environmental – combine to make people more or less susceptible to harm.
- Physical factors
Physical factors
For example, poor design and construction of buildings and unregulated land use planning.
From the research · Transport
Transport infrastructure such as roads, railways, ports, airports and inland waterways faces unprecedented challenges in a shifting climate, yet adapting transport systems has received limited attention. To bridge this gap, the UN Economic Commission for Europe (UNECE) published a study that identifies critical sections of the primary inland transport networks in the Pan-European region and Canada where the potential impact of climate risks is likely to grow. See more about the transport sector.
- Social factors
Social factors
For example, poverty and inequality, marginalisation, social exclusion and discrimination by gender, social status, disability and age, as well as psychological factors.
From the research · Older people and heat
People aged 65 and above are particularly susceptible to extreme temperatures. Heatwaves and cold waves are linked to increased respiratory and cardiovascular disease among older adults, yet only a few vulnerability assessments delve into hot or cold weather.
Researchers used an asset-based approach to create a General Vulnerability Index for older adults, covering human, financial, physical, place-based and social assets such as health status, education level and access to public services.
- Informational factors
Informational factors
When communication is designed for monolingual, digitally connected, institutionally trusting populations, it does not simply fail to reach others. It actively converts social differences into disaster vulnerability.
From the research · 2023 Mortegliano hailstorm, Italy
Barriers to timely, understandable information may be linked to language, disability, digital access, social isolation or limited trust. A study of the Mortegliano hailstorm found that vulnerable people often relied on informal networks to compensate for gaps in institutional communication, which shifted the burden of inclusive communication to already-marginalised communities.
Vulnerability is actively produced through communicative inequity, not just informational imbalance: media invisibility justifies institutional inaction, which pushes communities onto unofficial networks that institutions and the media cannot see.
Access the Disaster Risk Communication hub for practical guidance and tools for effective risk communication.
- Economic factors
Economic factors
For example, the uninsured informal sector, vulnerable rural livelihoods, dependence on single industries, and globalisation of business and supply chains.
From the research · Food supply chains
Countries increasingly depend on each other through complex, interconnected food supply chains. The COVID-19 pandemic exposed the entire process of bringing food from farms to tables to potential disruption. A study has investigated strategies to make food supply chains resilient to environmental shocks.
- Environmental factors
Environmental factors
For example, poor environmental management, overconsumption of natural resources, decline of risk-regulating ecosystem services, and climate change.
From the research · Heat and air pollution
A USC research team analysed six years of data on air quality, temperature and death certificates. Compared to ordinary days, the risk of death rises by 6.1% on extreme heat days and 5% on extreme air pollution days. When both occur together, the risk of death surges to 21%, nearly double the combined individual effects.
Vulnerability is also determined by historical, political, cultural, institutional and natural resource processes. These produce unsafe conditions such as living in dangerous locations or poor housing, ill-health, political tensions, or a lack of local institutions and preparedness.
Many underlying drivers, including poorly managed urban development, are increasing. While wealthier, well-governed countries are able to reduce disaster risk, some countries have grown rapidly without a commensurate reduction in vulnerability.
How humanitarian assistance can deepen vulnerability
Treating the biggest losses as the greatest vulnerability tends to favour people who own more.
Research · Who is counted
Losses are not the same as vulnerability
A simplistic understanding – that people with higher losses are more vulnerable and deserve more assistance – tends to favour well-off people, who own (and lose) more physical assets. Elites can use this to privilege themselves in benefits and influence.
Research · Who sets the agenda
External dependence narrows local understanding
When local humanitarian organisations rely on governments and donors for funding and legitimacy, they may miss the socio-political drivers of vulnerability and reinforce inequitable village-level and cross-scalar authority relations.
Read the paper on humanitarian assistance and vulnerability.
Why does vulnerability matter?
It explains why some non-extreme hazards lead to extreme disasters, while some extreme events do not.
Including vulnerability in our understanding of disaster risk acknowledges that disaster risk depends not only on the severity of a hazard or the number of people or assets exposed, but on their susceptibility to suffer loss and damage. In the context of extensive risk in particular, people's vulnerability is often the greatest factor in determining their risk.
Some groups are more susceptible to damage, loss and suffering than others, and within those groups some people experience higher levels of vulnerability. Vulnerable groups find it hardest to reconstruct their livelihoods after a disaster, which makes them more vulnerable to the next hazard event.
To reduce disaster risk, we have to reduce vulnerability.
Who is left behind: inclusion in practice
How do we measure vulnerability?
There is no single method: vulnerability works at many levels, changes over time and is not always visible.
Vulnerability is complex. It is driven by factors from local to global, and it alters under the pressure of those drivers. The chain of causes, from underlying drivers (such as socio-economic processes) to immediate conditions (such as poor-quality housing), can be long and complex. Tracking it shows where pressures can be released along the causal chain.
Any assessment should ideally be holistic. In reality, methods are usually divided into two:
What is physical vulnerability?
Assessing the vulnerability of the built environment means knowing how buildings respond to ground shaking or cyclone winds. Engineers in the Philippines and Indonesia are developing calculations for their own building stock, but these remain the exception. This information can only be reliably developed at the local level.
What is socio-economic vulnerability?
Efforts to quantify socio-economic vulnerability and poverty remain limited and are rarely integrated into risk assessments. Indicators range from global to community level and track change over time. See the GEM Global Social Vulnerability map.
Vulnerability and capacity assessments
At community level, researchers, non-governmental organisations and some local governments run vulnerability and capacity assessments (VCA), mainly through participatory methods. VCA is approached through a number of frameworks. According to Benson, it is typically applied as:
- A diagnostic tool to understand problems and their underlying causes
- A planning tool to prioritise and sequence actions and inputs
- A risk assessment tool to help assess specific risks
- A tool for empowering and mobilising vulnerable communities
Vulnerability analysis is about root causes, but also people's capacities to cope and recover. By identifying both, communities find what they can do themselves and where they need outside resources and assistance.
How do we reduce vulnerability?
We cannot stop hazards, but we can reduce vulnerability – at local, national and international scales.
Reducing vulnerability is one of the main opportunities for reducing disaster risk. Vulnerability changes because the processes behind it are dynamic, including rapid urbanisation, environmental degradation, market conditions and demographic change. Many are rooted in local conditions, but national and global socio-economic and political structures also constrain local development.
Approaches to vulnerability reduction include:
- Implementing building codes
- Insurance and social protection
- Emphasising economic diversity and resilient livelihoods
- Knowledge and awareness raising
- Preparedness measures
Start from capacity
Rather than focusing only on what limits people, disaster risk reduction (DRR) emphasises people's capacity to resist and recover from disasters. The local and traditional knowledge of vulnerable communities should form the basis of outside interventions.
Sustainable DRR capacity must be locally generated, owned and sustained, while remaining the concern of society rather than any single agency. It requires technical capacities, such as environmental management, but also leadership and managerial skills – and an enabling environment of strong political ownership and commitment at the highest level.
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Last updated: 9 November 2026