Access to and use of natural resources – like water and land for grazing or crop production – are key sources of conflict. Already in 2002, a joint study by FAO and IIASA highlighted how natural resources were shrinking [2]. More recently, FAO alerted about the risk associated with the incremental demand for food that, together with demand from other competing uses, will place unprecedented pressure on many agricultural production systems across the world. These 'systems at risk' are facing growing competition for land and water resources and they are often constrained by unsustainable agricultural practice [3].

The increasing world population [4] and its corresponding food insecurity will increase the pressure over those limited resources for several decades yet [5]. Resources pressures will intensify as  (very) limited public and financial resources for restoring degraded land and soils throughout the world become more and more scarce.

Other demands from industries, investors engaged extractive activities, recreational use and the expansion of urban settlements for increasingly limited natural resources (not only land, but also water and forests) will probably have dramatic effects in terms of disputes and conflicts over the resources. Decreasing governance capacities are also a potential driver for conflicts. As Hegre and Alii report, “[a]ny reform that improves governance may be conflict-reducing, be it to the formal political institutions, bureaucratic quality, or corruption”[6].

When people are forced to move, they abandon their physical assets such as land and property, and only carry their skills and movable assets such as livestock. Access to water becomes a critical problem, most particularly in areas where natural disasters (such as hydrological extremes) are combined with armed conflict. In such situations, traditional transhumance coping mechanisms are no longer viable.

The conclusions that can be drawn are: (i) much of the land most suitable for food and feed crops is already in use or no longer available; (ii) arable lands are lost to erosion, salinity, desertification and urban spread; forests disappear and biodiversity is lost. About 40 percent of the world’s arable land is degraded to some degree and will be further impacted by climate change, expected extreme weather events and climate variability; and (iii) biofuels add to the competition for land and water.

Land and natural resources come under greater pressure in cases of crisis and resettlement. Without a proper assessment of what land and natural resources are avaialble, how these resources aer used and governed, and by whom, it is impossible to achieve sustainable humanitarian interventions. This is especially true in protracted crisis contexts where the aim of interventions is to increase self-reliance and resilience, not only through food aid, but also through providing inputs and alternative livelihood sources.

The importance of land rights in post-conflict resettlement is often not recognized early enough as an issue of concern affecting internally displaced persons (IDPs) and hosting communities. And even when it is recognized, it is often politically unfeasible to effectively address those issues in the early stages of the post -conflict period. For example, Rwanda’s civil war saw Byumba, Butare and Ruhengeni Prefectures host up to 1 million IDPs in post-conflict resettlement areas. The hosting communities perceived the IDPs as an imposition or as “external foreigners imposed on them by the Government”. Such perceptions contributed to local tensions and “flare-ups” that strained already scarce resources [9].

IDPs reintegration in post-conflict areas remains as a considerable challenge for governments, especially after the initial emergency humanitarian assistance ends. Competition over natural resources and land in particular has been a critical cause of renewed violence, massive population movement and forcible displacements in post-conflict Uganda and Burundi. Competition for access and control of natural resources has become a source of tension and conflict in many other countries/regions, including Darfur, Liberia and Democratic Republic of Congo (DRC), especially in the last two decades [10].

The drivers of conflicts range from geopolitical interests, control over natural resources, ethnic tensions, religious differences, discrimination, poor governance, limited state capacity, population pressure and rapid urbanization, through to other factors such as poverty and youth unemployment. The nature and source of tenure disputes [11] and conflicts [12] differ by country and region (for example, in Asia, forest lands are very often at the core of the problem [13]. However, some common elements can be found:

1. Community social structures have historically been responsible and able to deal with dispute/conflict resolution [14]. In many countries in the South,  land-related government institutions de facto relied upon customary institutions to deal with these issues [15].
2. The parallel process of increasing interest over land (and other natural resources) in the last decade or so (with a direct link with the international financial crisis and the rising prices of commodities) and the parallel weakening of the customary institutions, has paved the way for more numerous and more complex disputes and conflicts [16].
3. The weakening of the customary institutions [17] is the product of several streams: first of all the rich and varying tenure arrangements historically conceived and put in place by those institutionsproved to be flexible and socially legitimate enough to deal with land conflict issues for centuries. The positive legislation (coming from both British common law and from French Napoleonian code) being more simple and less flexible had problems adapting to the diversity and flexibility of existing customary tenure arrangements. As a result, due to power asymmetries existing between colonial forces and colonized populations, the colonial forces were able to facilitate the integration of southern country resources into northern dominated markets. Legal reforms carried semantic changes (categorizing the customary institutions as “traditional” – meaning old fashioned, backward; in opposition to the “modern” institutions in charge of development) [18].
4. "Modern” land administration systems are  implemented through government institutions that, because of their weaknesses, are more vulernable to corruption and bribes and easily amenable to the demands of private investors [19].
5. To accelerate this trend, in the absence of any international recognized and respected standards, private companies (in many different economic areas, including mining, tourism and pothers) and investors with low reputational exposure, including many companies headquartered in emerging markets, have shown little inclination to address tenure issues through a direct dialogue with local right holders [20]. According to a recent study by Rights and Resources Initiative and Bharti Institute of Public Policy, “While official reasons given for stalled projects remain opaque, deep contestation leading to conflict on public (and private) lands must be better understood as a substantive risk to investments.” [21].
6. What is seen more and more as a common feature is governments not respecting historical customary rights [22] and becoming agents of foreign companies and investors [23]. Land disputes and land grabs appear more and more in post-disaster situations, as the case of Tsunami has shown [24] and in post-conflict areas, where displaced populations are returning [25].
7. In recent years, beyond agricultural land, conflicts involving pastureland used by pastoralists and nomadic people have gained attention [26].
8. Some proposed solutions should be cited: progressive legislation promoting the recognition of historical land rights was passed in Mozambique, however  more needs to be done to ensure this legislation is implemented [27]. Similar solutions to land conflicts have been proposed (but not yet agreed) in the case of Timor Leste [28].

Land-related conflicts occur in an increasing number of countries as a result of a combination of many drivers, including the asymmetry of information about rights, ambiguities in the legal framework on several matters, and the inobservance of the law and land administration procedures due to a combination of corruption, dirigisme, capacity constraints and negligence. The UN system [29]  is becoming more and more aware of the complexity (on the link between climate change and conflicts, see:  Climate Change, Security Risks and Conflict Reduction in Africa [30] and magnitude of the problem, particularly in view of the link with food security) [31]. Technical agencies are already intensifying their work on this issue (FAO is preparing a Corporate Framework on this. Un-Habitat/GLTN, with a series of partners, have launched an International Land and Conflict Coalition [32]. Other global NGOs [33] and donors are also doing important work to address land conflict issues [34].