This publication presents the results of the first global assessment of trees, forests and land use in drylands, arid areas that cover 41 percent of the Earth's land surface. Using the Open Foris Collect Earth tool, developed by FAO in collaboration with Google, the assessment breaks new methodological ground: it relies on the analysis of freely available satellite images by more than 200 experts for some 200000 plots worldwide. For each region, the report summarizes the distribution of forests, other wooded land and other land uses including grasslands, croplands, built-up areas and barren land, across all drylands and by aridity zone. It also estimates tree canopy cover, shrub cover, forest type and the presence of trees outside forests. While revealing that global drylands contain more than one-quarter of the world's forest area, the report provides a baseline for future monitoring and will support countries in their efforts to identify appropriate investments for the restoration and sustainable management of drylands.