Flow cytometry is a rapid method with many microbiological applications. This technique can be used to obtain counts of viable yeasts in 30 min, whereas a 48 h incubation is necessary with plate counts. This rapid method was tested for its suitability to analyse wine yeasts in a multicentre study in our three laboratories. The study compares measurements obtained by flow cytometry and the usual method, in order to test the reliability of the new method. The results obtained were very similar in terms of both the micro‐organisms detected and the precision of measurements.