SUMMARY In a regional quality survey programme in haematology with a limited number of participants (15 in the region described), it appeared possible to use unpreserved, fresh, EDTAanticoagulated blood samples. With such samples only the results from hospital laboratories with different instruments and methods could adequately be compared. From the results of single analyses obtained in ten different samples, the systematic differences as well as the precision of the analyses were calculated for each hospital laboratory with respect to haemoglobin, packed cell volume, red blood cell count, white blood cell count, and platelet count.