This chapter describes several assessment methods in terms of how they select and measure environmental attributes, rank the attributes on personal or social preference scales, display the results, and are related to other methods. Environmental assessment involves weighing both facts and values. The metropolitan landscape planning model (METLAND) presents spatial information on the comparability of land use developments and environmental quality. METLAND consists of three phases: composite assessment, alternative plan formulation, and evaluation. The evaluation and weighting steps are combined to obtain commensurable environmental impact units by multiplying the scaled values and the associated parameter importance unit weights. METLAND has been applied to an area of approximately 80 square miles, comprising three small towns in Franklin County, Massachusetts: Bernardston, Greenfield, and Deerfield. METLAND depends on technical experts; participation by decision makers or publics is limited to an after-the-fact review. Conceivably, the roles of publics and decision makers could be expanded through surveys to find the relative importance weights.