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The PAGE reports analyze quantitative and qualitative information and develops indicators of the condition of the world's freshwater, coastal, forests, grassland and agroecosystems. The condition is defined as the current and future capacity of the systems to continue providing the full range of goods and services needed or valued by humans.

The PAGE: Forests ecosystems examines the spatial extent of forests and the degree of human modifications on their extent and structure over time. It also looks at measures of condition concerning five important goods and services: industrial roundwood and woodfuel production, biodiversity, carbon storage and sequestration, and watershed protection. The choice of goods and services was determined partly in consultation with forestry experts in many countries and partly by data availability.

Results of the analysis show that global forest cover has been reduced by between 20 and 50 percent since preagricultural times.

• Nearly all forests in Europe and the United States are under management and support reduced levels of biodiversity.
• Loss and degradation of tropical forest is more severe than official estimates imply because zones of mixed forest and agriculture are spreading rapidly at the borders of formerly intact forests; these zones usually support enough trees to classify as forest although their capacity to provide the full range of forest goods and services may be greatly reduced.
• The world's growing road network poses a major threat to forest condition because they provide access for development and increase hunting and poaching.
• Logging continues to degrade mature forests, despite the growing importance of wood plantations as a source of supply.
• Demand for wood and pulp is growing rapidly, and could lead to exploitation of currently remote forests, especially in Siberia, Central Africa and the Amazon basin.