Indexes For Fixed And Flexible Environmental Target Setting: A Decision Analytical Perspective

We describe a decision-analytical, structured approach for developing environmental indexes, ensuring them to be explicit and problem-specific. The indexes are used for setting and communicating targets related to a product's environmental performance. Two index models are the fixed model, based on the prevailing tradition, where announced targets must be met in every impact category, and the flexible model, where impacts are aggregated and a target is announced in terms of the aggregated impact, thus enabling trade-offs between the impacts. The flexible model is a new and promising approach, which offers more freedom to reach the target even though more preference information must be modelled. We stress the different viewpoints of those using the index for target setting and of those whose products are evaluated with the index. We do this by differentiating between impacts and stressors and expressing the targets in terms of both. We illustrate the approaches with a hypothetical environmental labelling example.