railis report focuses on agricultural drainage and salinity problems associated with irrigated agriculture in the Central Valley of California. The development of irrigated agriculture in that region is described, along with the evolution of the drainage-salinity problems. Studies estimating the economic value of the damages and the social costs of solutions to the problems are discussed and compared. Physical, institutional, legal, and economic aspects are highlighted. Policy solutions need to take into account the complexity of the problem and the inability of a single measure to provide a comprehensive solution.