To ensure the water quality in Europe, the European Commission asked the member states to provide comparable and traceable measurement results for the analysis of critical pollutants. Considering the increasing environmental challenges, the contribution of metrology is necessary both for the improvement of analysis reliability and the comparability of results. For this reason the European research project Euramet/EMRP/ENV08 “Traceable measurements for monitoring critical pollutants under the European Water Framework Directive (WFD-2000/60/EC)”, funded by the EMRP, aimed to provide the elements for the development of a metrological basis. The project develops primary reference methods enabling the analysis of priority hazardous substances in order to meet the WFD requirements in terms of performance levels (limit of quantification and uncertainties). Polycyclic aromatic hydrocarbons (PAHs) – priority hazardous substances for which no DCE compatible methods exist – are among the three families of pollutants targeted by the project. This paper tackles the development and validation of the PAH analysis method on whole water samples. The method that best meets the requirements of the WFD in terms of level of concentration and uncertainty is the solid phase extraction (SPE) method with SPE-disks, followed by isotope dilution analysis combined with gas chromatography mass spectrometry (ID-GC/MS).