The first edition of this book appeared in 1982. In the preface to that first edi­ tion, I wrote This book is based on the lecture course in renal physiology which I give to medical students at the University of Birmingham. The pur­ pose of the book is primarily to set out the principles of renal physiology for preclinical medical students, and it is therefore concerned mainly with normal renal function. However, diseases or abnormalities in other body systems may lead to adaptations or modifications of renal function, so that a good knowl­ edge of renal physiology is essential to the understanding of many disease states, for example the oedema of heart failure or liver disease, or the conse­ quences of haemorrhage and shock. The new edition is still based on the lec­ tures which I continue to give at Birmingham University, but over the years the course has gradually changed, to being a system based course covering all aspects of the kidney - the anatomy, physiology, pharmacology and pathology. The new edition of the book, which has been extensively revised and rewritten, reflects this. However, it continues to offer a concise, easily readable format, primarily intended for undergraduate medical and medical science students.