The economic impact of reducing the amount of nitrate leached out of the root zone under irrigation in the arid West was examined. A general introduction into the nature of the problem and a review of the literature was provided in chapter I. In chapter ll the economic incentives of irrigation management were evaluated under the assumptions of both profit-maximizing and utility-maximizing (in reducing cost and effort expended in irrigation) decision-making criteria. The results indicate that there is a coincidence of interests of the farmer and the environment. Both behaviors result in less nitrate leaching than less profitable or less utilityproducing irrigating practices. In chapter lli the economic impact of reducing the amount of nitrate leached out of the root zone under irrigation with various nitrogen sources and application methods was examined. The economic incentives of nitrogen management were evaluated under the assumption of profit-maximizing behavior. The results indicate that there is a coincidence of interests for irrigators who respond to economic incentives and environmentalists who wish to reduce nitrate residuals in irrigation drainage and the groundwater. Profit-maximizing behavior results in less nitrate leaching than less profitable irrigating practices when salt balance is not a major concern.