This is a tutorial page, it should help those making an SoE report to better understand the ideas and concepts behind the SoE template. After the report is prepared, this page should be removed. At a later stage this can be automatically handled by the software, at the moment you will need to do it manually by deleting this file from your report's directory.

Indicators in the context of a state of the environment report are representative, concise and easy-to-interpret parameters which are used to illustrate main features of city environment.

The idea of an indicator was apparently derived from economic analysis where economic indicators such as GDP have been used for a long time. A set of indicators, if selected well, provides a shortened but nonetheless generally correct picture of a system. Besides, when combined with textual interpretation, indicators serve as "evidence" highlighting facts that confirm what is being said.

Indicators can either represent an issue in a broad sense (e.g. heavy metals in urban soils indicate the pattern of toxic pollution in general), or aggregate several pieces of information (e.g. a water quality index as a combination of several water quality parameters).

In a state of the environment report, indicator values can be presented in the form of numbers or as part of the text, but are much more powerful in a graphical form, e.g. as trend graphics, distribution maps, diagrams, etc. CEROI suggests two groups of indicators to be included in a city state of the environment report:

• A core set of indicators of a limited size (not more than 20-30) will be common for all, making it possible to compare some key values for the participating cities in an easy way. These indicators will be accessible both through respective cities' reports and through the central CEROI on-line database. The final list will be selected in close co-operation with participating cities, partner organisations and CEROI Advisory Board as much as possible taking into account international experience. In particular the list will be harmonised with ICLEI's Cities 21 indicators.

• City-specific indicators for individual themes will make up the main part of any city report. These indicators will be chosen by cities themselves depending on various criteria, not least local priorities and data availability. CEROI will however assist cities in selecting such indicators by developing lists of possible, or proposed, indicators for individual issues and themes in co-operation with project partners.