The new MassChrom kit from Chromsystems allows the reliable determination of EtG and EtS from urine with robustness and precision. The assay is validated according to the guidelines of the GTFCh (Society of Toxicological and Forensic Chemistry) for quality assurance and enables the determination of both parameters with one sample preparation and one single injection with an analysis time of 6 minutes. The straightforward and efficient sample preparation consists of a single pipetting step that includes the instrument-specific dilution. The human-matrix based 6PLUS1 Multilevel Calibrator Set and MassCheck controls ensure precision and accuracy of results. Typically, less than 0.1 % of the consumed ethanol is present as the glucurono- or sulpho-conjugated configuration, which is excreted as ethyl glucuronide (EtG) and ethyl sulphate (EtS), both detectable for a sustained period in comparison to ethanol. Thus, EtG and EtS close the gap between short-term markers (i.e. ethanol itself) and long-term markers such as carbohydrate deficient transferrin (CDT).