ABSTRACT
Social impact assessment (SIA) often makes use of the views of community leaders in the profiling and assessment process. It is being increasingly recognized that value judgments play a critical role in the SIA. One way to categorize and understand them is to suggest that there are two forms. The first, and least mentioned, are those internal to the SIA. In other words, the assessor's own values may often implicitly structure the nature of the SIA - often under a guise of neutrality. In addition to the internal values in SIA there is sometimes a call for external "value weights" to be developed as part of the analysis. These are attempts to explain the differential contribution of various impacts to the overall assessment. Value-weighting based on citizen preference is undertaken in two ways, first, by research analogous to what the economists term revealed preference, and second and more importantly, by directly developing citizen input to the assessment process.
