Desertification — the “creation” of a desert, perhaps by humans — is a highly contentious issue. Arguments surrounding this topic create confusion in policy and management programs intended to help many ofthe world’s poorest people. While climate is obviously a controlling influence on deserts, which occur naturally in dry areas, it is equally certain that humans and their agriculture and ranching practices have “caused” desertification in some places. However, there remains a great deal of disagreement about the causes and extent ofdesertif ication and, consequently, about what part ofits impact on human well-being is manageable and how. There is an urgent need for new, interdisciplinary approaches for addressing this global problem. We suggest that a new synthetic framework must be developed based on the unique and simultaneous roles ofthe meteorological and ecological dimensions of desertification (the biophysical factors) and the human dimensions of desertification (the socioeconomic factors). Previous failures to recognize and include the interdependencies of these dimensions in decision-making have slowed progress toward the synthetic approaches needed to tackle the enormous problem of dryland degradation.