Using data from field studies in the Kalahari rangelands of Southern Africa, the relationships between 'scientific' and 'land user' interpretations of land degradation and change in nonequilibrium savanna ecosystems are explored. Scientific and landuser views are often regarded as distinct, and even opposed, knowledges. We contest that a more constructive view can be taken through the concept of hybrid knowledge, whereby value is attached to both approaches and through which a more useful and meaningful assessment of environmental change, and its implications for development and natural resource use, can be made. We find that in both the southwestern and northwestern Kalahari, pastoralists have a complex understanding of the patchiness of ecosystem variability, and that they utilise elements of this patchiness of change, notably dimensions of bush encroachment and grass species change that have commonly been regarded as degradation in scientific understandings, within livestock management strategies, especially at times of environmental stress. Keywords: knowledge repertoires, hybrid knowledge, ecological change, land degradation, Kalahari, Southern Africa.