Abstract : The thrust of this study has been to pull together the state of the art and to synthesize a water resources assessment methodology (WRAM) for impact assessment and alternative evaluation. A review of 54 impact assessment methodologies revealed that none entirely satisfied the needs or requirements for the Corp's water resources projects and programs. However, salient features contained in several of the methodologies were considered pertinent for inclusion in WRAM. One of the features consisted of weighting impacted variables and scaling the impacts of alternatives. The resulting weighted and scaled values are multiplied to obtain final importance values. The weighted rankings technique is the basic weighting and scaling tool used in this methodology. It consists of developing relative improtance coefficient values for each variable, assigning alternative choice coefficient values to each alternative in relation to its impact on each variable, and displaying the products in a final coefficient matrix. Principal components of WRAM include assembling an interdisciplinary team; selecting and measuring assessment variables; identifying, predicting, and evaluating impacts and alternatives; and documenting the analysis. Although WRAM is presented for use by the Corps in water resources management, it does have general applicability to other resource management agencies.