THE PHILOSOPHY OF QUALITY ASSURANCE IN THE BLOOD BANK H. F. Taswell One year before this symposium, Cees Smit Sibinga and I began to discuss an approach to quality assurance in the blood bank which we felt would be both important and practical and could serve as the basis for the choice of subjects to be presented in the symposium. As an introduction to this book, I would like to outline our approach, the subjects chosen and the rationale behind our choice. What is the fundamental purpose of a blood bank and trans- fusion service? Simply stated, the purpose of a blood bank and transfusion service and of a quality assurance program in blood banking is, for the one to provide and, the other to assure safe and effective transfusion therapy. This objective is in contrast to that of other clinical laboratories. The objective in a clinical chemistry laboratory is to produce accurate test results which will be meaningful to the clinician taking care of his patient. In most clinical laboratories, therefore, the goals of a quality assurance program are largely quantitative, that is, to assure accurate numerical test results. In contrast, in the blood bank, the goals of quality assurance are primarily qualitative, that is, to assure safe and effective transfusion. As a result, two somewhat different approaches to quality assurance are necessary.