This research seeks to explore the complexity of human-land relations in the Aspre, with respect to land degradation. It is argued that in human modified environments, such as this Mediterranean-Pyrenean borderland, nature and culture cannot be meaningfully studied apart. Consequently issues of land degradation must be situated within the broader context of socio-natural interaction. Such a study cannot be approached solely from a natural or social science perspective; what is required, and what has been developed in this research, is a transdisciplinary methodology whereby natural phenomena are situated within their historical and socio-cultural context. Central to that context is the need to position the system within a long term evolutionary dynamic, thus allowing us to view the system in process, rather than as a synchronic present day snapshot. Within this 'longue duree' temporal and spatial scales are seen to be critical. It is argued that land degradation is at root a perceptual issue, thus perception and cognition are seen as critically important in this study. The core field work acts to expose both the physical and social identities of the Aspre, and the multiple perceptions of land degradation held by its inhabitants. The research identifies a series of 'perceptual filters' through which the environment of the Aspre is experienced, and by means of which meaning is negotiated. The recognition of the multiple environmental perceptions and plural rationalities is of crucial importance when contemplating the possible future pathways open to the Aspre, with respect to sustainable futures. What emerges from this research is a redefinition of land degradation in the Aspre, from that of a purely physical issue, to the realization that what we are dealing with are changing social identities within changing landscapes.