The lack of standard local values for use as reference values has been a problem facing our haematological units in Sierra Leone for a long time. As a preliminary step towards the establishment of standard local values, one hundred and sixty apparently healthy Sierra Leoneans between the ages of 10 years to 50 years and above living in Freetown were investigated for the determination of total and differential white blood cells counts. The total white cell count was done by using the neubeur counting chamber whilst the differential white cell count was done from a thin blood smear stained with leishman's stain. A mean white blood cell count of 5.0 x 10(9)/L was obtained for the study group with a range of 2.4-12.0 x 10(9)/L. The study did not show any significant difference in white blood cell count between males and females. A mean differential neutrophil count of 56% was obtained for the study group and a mean differential lymphocyte count of 37% were obtained for the study group. The leucopenia obtained for the study group is thought to be due to the neutropenia and is probably thought to be a genetically determined characteristic of the indigenous Africans.