Granulocyte concentrates contain varying numbers of platelets and red cells depending upon the method of collection. Either platelet or red cell concentrations may be as high as 2.0 X 10(12) per I. Studies were done on unwashed and washed granulocyte concentrates and on pure granulocyte suspensions with known numbers of platelets or red cells added. These suspensions or concentrates were stored for 72 hours at 22 degrees C. In both experiments, the following were measured: leukocyte and absolute granulocyte counts, dye exclusion, chemotaxis, plasma glucose, plasma pH, and osmolality. Red cell contamination did not adversely effect granulocyte storage. Platelets, however, did contribute to the functional deterioration of stored granulocytes. In the presence of high concentrations of platelets, both granulocyte dye exclusion and chemotaxis were adversely affected at 48 hours of storage. In another experiment, fresh autologous granulocytes incubated for 18 hours in hydroxyethyl starch-citrated-plasma obtained from stored granulocyte concentrates showed a progressive decrease in chemotaxis related to the age of the stored plasma. Glucose supplementation of the spent plasma maintained chemotactic activity. Contamination of granulocyte concentrates with other cells and the availability of glucose to granulocytes are variables affecting the short-term liquid storage of granulocytes at 22 degrees C.