The Environmental Quality Standards Directive 2008/105/EC (EQSD) marks an important step in the use of sediments and biota as matrices for chemical-status assessment under the Water Framework Directive 2000/60/EC (WFD). Analysis of contaminants in sediments and biota is indeed widely recognized as a cost-effective approach in water-quality monitoring to describe the general contamination level, to supply reference values for local and regional monitoring and to identify areas of concern where additional monitoring effort is needed. Because of the explicit reference in the EQSD to the use of sediments and biota as preferred matrices for the monitoring of substances with accumulation potential - especially for the assessment of long-term trends, but also for compliance checking, wherever appropriate - Member States of the European Union (EU) asked the European Commission to publish a guidance document to enhance the degree of harmonization among EU countries in chemical monitoring of sediments and biota, taking into account best available techniques, standard procedures and common practices. This article presents the key features of that guidance document, its main recommendations for chemical monitoring of sediments and biota and the scope for further improvement in current monitoring practices.