The project will follow the rapidly changing conditions produced by the fifth year of drought in California and will collect data which otherwise would be lost. The study will focus on the following four areas: a) the acquisition and analysis of drought- related meteorological and hydrological data in order to assess the uniqueness of this drought episode; b) the assessment of the drought monitoring procedures in order to determine how efficiently the drought's beginning was detected and the drought's progression was evaluated; c) the assessment of the effect of the drought on the performance of major water resource engineering projects; and d) the assessment of the performance of unusual response measures, e.g., water transfers and water banking. The results of this work will benefit climatologists, hydrologists, planners and managers, and researchers from government, the private sector and academia.