After many years of relative neglect, the importance of study of factors governing blood flow has at last achieved recognition; in this volume are documented many of the techniques, and the basic scientific and clinical observations, which have helped to open up understanding of this highly important aspect of human physiology and pathology in recent years. The text is logically divided into five sections beginning with blood cell deformability, then moving on to theoretical consideration of blood rheology, followed by accounts of the interrelationships between rheology, blood flow and vascular occlusion. The final two sections deal with blood rheology in clinical practice and therapeutic aspects of the study of blood flow. As regards blood cell deformability (Section A), the basic problem is set out by Kiesewetter and colleagues in the first paragraph of chapter 1 (p. 3), in which they point out that whereas human erythrocytes at rest have a diameter of approxi mately 7. 5 /-tm, nutritive capillaries have diameters ranging from 3-5 /-tm, and chapters in section A give an account of the ways in which the red cell can undergo deformation to permit capillary perfusion and the maintenance of the microcirculation."

These proceedings are of a symposium held jointly by the UK Haemophilia Centre Directors and the Royal College of Physicians and Surgeons of Glasgow. The purpose of the meeting was to highlight the growing areas of haemophilia care and research as they serve as a model for the study of other disorders. In particular a major section of these proceedings is devoted to the investigation of liver disease in haemophili- an area which offers unique opportunities for both basic, applied and clinical research. The second section considers modern treatment of bleeding disorders and the potential cost to society. With the advent of better standards of care, the requirements of plasma products have risen to such an extent that future predictions suggest a worldwide shortage may occur. The third section of the book discusses the detailed structure of the Factor VIII molecule and its sub-compon( nts and also its functional and immunological characteristics. The availability of amniocentesis and its accuracy in predicting which factor is affected has produced new problems for genetic counselling. The fourth section is clinical and describes the experience of procedures in the Nuffield Department of Orthopaedics, Oxford. For all of us looking after such patients this remains the most important unsolved cI inical problem. C. D. Forbes G. D. O. Lowe vii List of Contributors Professor Charles Abildgaard, Dr. Geijlswijk, Department of Paediatrics, Department of Haematology, 4301 X Street, University Hospital, Sacramento, Utrecht, California 95817 The Netherlands Dr. L.