The idea for this book arose from an integrated Iecture course on the biochemistry of blood given to medical students in the second year of their pre-clinical studies. However, the material in that course has been expanded and it is intended that the book provide both the medical and non-medical reader with a concise and up-to-date account of the status of knowiedge of the biochemistry of blood. A glance at the chapter titles shows how wide a field this covers, including many of the growth areas in biochemistry. It is assumed that readers of the book will have a basic knowiedge of biochemistry. A functional approach is, adopted, and whenever possible the material is organised in terms of biochemical functions, although there are separate chapters on the white cell and the red cello Because of the clinical importance of analysing blood components and assaying enzymes in the diagnosis of disease, chapters are included on the separation, preparation and measurement of blood components.