The inherent dangers of using computable general equilibrium models as a single integrated modelling framework for sustainability impact assessment. A critical note on Böhringer and Löschel (2006)

The search for methods of assessment that best evaluate and integrate the trade-offs and interactions between the economic, environmental and social components of development has been receiving a new impetus due to the requirement that sustainability concerns be incorporated into the policy formulation process. A paper forthcoming in Ecological Economics Böhringer, C., Löschel, A., in press. Computable general equilibrium models for sustainability impact assessment: status quo and prospects, Ecological Economics.] claims that Computable General Equilibrium (CGE) models may potentially represent the much needed “back-bone” tool to carry out reliable integrated quantitative Sustainability Impact Assessments (SIAs). While acknowledging the usefulness of CGE models for some dimensions of SIA, this commentary questions the legitimacy of employing this particular economic modelling tool as a single integrating modelling framework for a comprehensive evaluation of the multi-dimensional, dynamic and complex interactions between policy and sustainability. It discusses several inherent dangers associated with the advocated prospects for the CGE modelling approach to contribute to comprehensive and reliable sustainability impact assessments. The paper warns that this reductionist viewpoint may seriously infringe upon the basic values underpinning the SIA process, namely a transparent, heterogeneous, balanced, inter-disciplinary, consultative and participatory take to policy evaluation and building of the evidence-base.