Drylands, comprising deserts, grasslands and woodlands, cover about 41 per cent of the Earth's land surface and are inhabited by more than 2 billion people—about one third of the world's population. Many of these drylands face severe degradation, in which marginal areas are turned into wastelands and natural ecosystems are altered through destruction of surface vegetation, poor management of water resources, inappropriate land-use practices, overuse of fertilizers and biocides, and disposal of domestic and industrial wastes. As a result, populations in the drylands on average lag far behind the rest of the world on human well-being and development indicators. In the absence of any remedial measures, the situation is likely to get worse over time due to population increase, land-cover change and global climate change. The exact numbers are, however, still not known and experts have not come to a complete consensus on the severity of desertification.

A new analysis by the United Nations University (UNU), presented at UN Headquarters on 28 June 2007, sees desertification as "the greatest environmental challenge of our times" and demands Governments to overhaul policy approaches to the issue or face migration of people driven from degraded homeland within a single generation. UNU experts say the loss of soil productivity and the degradation of life-support services provided by nature pose imminent threats to international stability. The new strategy by the UNU International Network on Water, Environment and Health (UNU-INWEH) attempts to make better known the severe effects desertification can cause and to bring understanding and support to those in need of help. Although desertification is widely understood to be caused by humans and land degradation practices, with climate change exacerbating and only playing a minimum role, many Governments have not established sufficient action plans in the fight against desertification.

It is indeed a wide-ranging and very serious problem. A major and severe consequence of land degradation and desertification is the displacement of people. Desertification has caused major disruptive patterns and will continue to increase the number of migrants, who are being displaced due to environmental causes. "Desertification is one of the most pressing global challenges taking place faster than it historically has, and by inherently destabilizing countries internally puts over 50 million people at risk over the next ten years", said Peter Marcotullio, Adjunct Senior Fellow for the UNU Institute of Advanced Studies (UNU-IAS). Besides having social impacts, the economic impacts of desertification are grave too. It is estimated that it leads to an annual income loss of over $65 billion.

A UNU-INWEH programme assists developing countries in dryland areas to better manage their land resources and to achieve sustainable use of water and biodiversity resources. This is done through capacity-building at various scales, ranging from community-based efforts to national training initiatives. The capacity-building efforts are closely interlinked to knowledge management to support national policy development, particularly in relation to poverty reduction strategies and better integrated natural resource management. UNU-INWEH Director Zafar Adeel pointed to clear challenges: "Desertification is a stumbling block to achieving the Millennium Development Goals and rolls back much development that may have already been achieved. The challenge is that we don't know for a fact about desertification, which in turn makes it challenging to propose policy options. On the one hand, we are thinking, the problem is getting bigger, while one the other, resources to combat it are shrinking." Desertification represents interlinkages with other global and development issues: "Land degradation, climate change and biodiversity losses exacerbate other salient development issues, such as food security, famine conflict and health."

UNU-INWEH has registered minor successes in the fight against desertification. "We have seen small success stories. Now, we must find out why these stories constitute success, better understand them and then build on them", said Caroline King, Project Officer for UNU-INWEH. However, desertification shows no sign of abatement. UNU attributes the main barrier to expanding isolated regional successes at combating the problem as the lack of effective management policies. "There needs to be a new direction and reorientation of existing institutions, in order to achieve capacity-building for developmental policies. Job alternatives and sustainable livelihoods need to be created", Mr. Adeel said. In illustrating desertification as a widespread problem, he added that the "problem and solution are often even similar across socio-economic divides".

"Desertification is a problem of global proportions", according to Mohamed Sofiane Berrah of the Permanent Mission of Algeria to the United Nations, a country affected by it. "The problem of desertification and the situation of land degradation that the world currently faces are preventable and we can protect drylands. What is required, are long-term strategies and actionable policies."