Definitions of indicator within the COST action 356 EST

International audienceAfter a presentation of the objective of the COST action EST "Towards the definition of a measurable environmentally sustainable transport", the literature has been reviewed to identify some potentially relevant definitions of the term ‘indicator’, to help identify the key functions that indicators can play, and revel the extent to which context factors should be allowed to influence the definition of indicators. The review of indicator definitions considers general or generic indicator definitions, the definitions of ‘environmental’ indicators, the indicator definitions that take into account the context of sustainability, and the indicator definitions that have been proposed within the specific field of sustainable transport. A definition is proposed in conclusion