1 Tradeoff Assessment as a Quantitative Approach to Agricultural/Environmental Policy Analysis John M. Antle Department of Agricultural Economics and Economics Montana State University Jetse J. Stoorvogel Laboratory of Soil Science and Geology Wageningen University Charles C. Crissman International Potato Center Walter Bowen International Potato Center and International Fertilizer Development Center Introduction This chapter discusses tradeoff assessment as an organizing concept for a quantitative approach to ecoregional research and agricultural/environmental policy analysis. Motivating this approach is the view that quantifying tradeoffs is an essential ingredient in setting research priorities and in designing and implementing the criteria of sustainable agriculture in agricultural research programs, as described in detail in Crissman, Antle and Capalbo (1998). This chapter also provides an introduction to a modeling system (the Tradeoff Model) being developed as a decision support tool for agricultural and environmental policy analysis and policy decision-making (Stoorvogel, Antle, Crissman, and Bowen, 2000). This modeling system is designed specifically to integrate disciplinary data and models at the field scale, and aggregate economic and environmental outcomes to a scale relevant to policy analysis, in order to quantify tradeoffs between competing economic and environmental policy objectives. The ultimate goal of the research programs supporting the development of the Tradeoff Model is to construct a flexible tool that can be used to integrate disciplinary data and models to provide information about agricultural production systems needed by policy decisionmakers. The goal is to develop a tool that can be used by a team of disciplinary researchers and adapted to fit any production system. The modeling system described here is a prototype of this type of policy decision support system. It is designed to represent a specific production system – the potato/pasture system typical of the equatorial Andes. The objective of ongoing research is to develop methods for generalizing the structure of the system and for simplifying the model components to the degree possible while maintaining the degree of accuracy needed for policy analysis. Tradeoff assessment provides an organizing principle and conceptual model for the design and organization of multi-disciplinary research projects to quantify and assess competing objectives in agricultural production systems. This process is illustrated in Figure 1. Input from the general public