Directive IVD 98/79 EC and standard ISO 15189 can be regarded the main current key documents to evidence of competence and profesional proficiency. While ISO 15189 is in fact tool for assessing the proficiency of individual laboratories, Directive 98/79 EC defines requirements on the manufacturers of IVD for their implementation on European market. This communication deals with role of Directive, its relationship to validation, traceability and uncertainty of results/methods/measurements. Final target of Directive should be comparability of measurements, providing the validated IVD products, assuring the commonly accepted reference intervals and also creating the realible functioned quality control systems. Realisation of traceability via proper calibration is way to reaching this aim. Communication is writen from point of wiew of the laboratory scientist and introduced some possible discrepancies between laboratory and manufacturers/suppliers.

        Key words: Directive 98/79 EC, metrology, comparability, validation, proficiency.