The Nordic countries have a common goal to halt the decline in biological diversity by 2010. Indicators and indices are important tools to describe the development in biodiversity and hence evaluate the 2010-target.

At a workshop held in March 2006, the quality, availability and policy relevance of biodiversity data in the Nordic countries were evaluated. Available data differ between countries but it was agreed that the overall quality of the data allows the development of an aggregated index (and a set of indicators) that can describe the state of biodiversity in the Nordic countries.

In a Nordic biodiversity index, quantity of biodiversity should be measured as total area of each habitat type, both inside and outside protected areas. Quality should be measured as species abundance and, when applicable, as species composition and/or habitat structure (e.g. dead wood). The index should be illustrative, easily understood and based on transparent calculations and assumptions.