Soil salinity and waterlogging and other forms of land degradation reduce the agricultural productivity and farm income, while threatening the sustainability of agriculture in many areas. The purpose of the Study is to estimate the economic impacts of land degradation on cotton production in the Gediz Delta, Turkey, where salinization and waterlogging threaten the sustainability of irrigated agriculture. Salinity and waterlogging have developed over time in the region, due to unfavorable use of irrigation water and inadequate drainage. We use data collected in a Survey of farmers in the region to estimate regression models for cotton production on degraded and non-degraded soils. We conclude that cotton yields are reduced by 34.4% and gross margins are reduced by $860.2/ha, as a result of land degradation. (c) 2004 Elsevier Ltd. All rights reserved.