In order to reflect the mandate of the International Geographical Union's (IGU) Commission on Land Degradation (COMLAND), this special issue of Land Degradation & Development is entitled 'land degradation and mitigation'. COMLAND exists to promote and coordinate interdisciplinary research on land degradation and desertification in a changing global environment. That changing environment now recognises that to mitigate land degradation there must be a close understanding of the processes, extent, rate and impact of degradation-all aspects which members of COMLAND have sought to research and publish (see the COMLAND website-http:// www.ub.es/gram/COMMAND%20website/).
The papers in this issue were selected from the 30 presented at a COMLAND conference held in Reykjavı ´k, Iceland, 16-23 August, 2003 entitled Land Degradation and Mitigation, Problems-Conflicts-Solutions (Gisladottir 2003). They collectively demonstrate the variety and variability of issues related to land degradation and its management, and the way that geographers of the IGU now interact closely with professionals from engineering, agriculture, development and the social and natural sciences generally.
Land degradation has been on the agenda of the IGU for at least 12 years. COMLAND's predecessor in 1992 was a Study Group on Erosion and Desertification in Regions of Mediterranean-type climate (MED), chaired by Dr Maria Sala from the University of Barcelona. The focus was on understanding the cultural and biophysical contexts as well as the nature and extent of land degradation, and on discussing solutions. In 1996, the MED Study Group became a full Commission of the IGU, with Dr Sala as its first Chair. She was succeeded in 2000 by Prof. Moshe Inbar from the University of Haifa, but continues her active involvement in COMLAND's work. Under the chairmanship of these two geographers, the perspectives of COMLAND have broadened to encompass interdisciplinary research on land degradation and desertification throughout the world. Research by members of COMLAND has included work on land degradation processes, land degradation as a response to land-use practices and land-use change, the societal implications of land degradation, rehabilitation of degraded land, and the development of policy. While retaining the Commission's original grounding in geomorphology, the focus is increasingly turning towards the management of land degradation, including an increased incorporation of social sciences.