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This work focuses on determining the performance in terms of technical efficiency of oasis irrigation in southern Tunisia using a parametric stochastic frontier approach. Date palm yield is explained by four factors: water quantity applied, labor, farmyard manure, and phosphate. The elasticity of demand for irrigation water is estimated to be-1.17; this leads us to suggest that appropriate pricing of irrigation water could contribute to the conservation of this increasingly rare resource. Further, estimation of the technical inefficiency model shows that salinization has a negative impact on technical efficiency. The mean value of technical efficiency is estimated to be 0.653.