A volume on the biliary system appeared in 1965, based on a symposium of the NATO Advanced Institute held in September, 1963, in Newcastle upon Tyne in England. It soon became an authorita tive text on the problems of the biliary tract and, for instance, the discussion on the biliary secretion of organic anions, organic cations and inorganic ions were classic references. The worn pages of the volume in many libraries, including my own, bespeak its usefulness over ten long years. The initiative and energy of the Director of the first Institute have to be admired, even more so since he was able to assemble a Second Institute in Aalborg, Denmark, in 1975. His wisdom is reflected in the selection of the subjects discussed. The comparison between the two volumes tells something about the advancement in the time interval in knowledge about liver and biliary tract diseases, about the turnover of researchers interested in the liver and its diseases, and also about the present philosophy in biologic science. For this com parison, this volume is particularly suited because, in contrast to many other recent conferences, the more leisurely pace of the NATO Institutes permits more comprehensive but still scholarly reviews of the problems. The foreword of the first volume, written by my colleague, the late Harry Sobotka, expresses his, now dated, astonishment about the progress of knowledge of biology of the bile, so much less accessible to study than urine.

Inhalt
by the Director The Hepatobiliary System: Retrospect and Prospect A Personal View.- Session 1 Membranes and Transport Mechanisms.- Membrane Structure.- Transport Through Biological Membranes.- Mechanism of Transport of Inorganic Ions into Bile.- Biochemical Studies on Bile Secretion.- On the Structure and Function of Ligandin and Z Protein.- Excretion of Xenobiotic Compounds in Bile.- Session 2 Structure and Function in the Hepatobiliary System.- The Fine Structure of Liver Cells.- Ultrastructural Changes Induced by Drugs.- Liver Damage and Regeneration after Poisoning.- Toxic Effects of Lithocholate on the Liver and Biliary Tree.- Fine Structure of the Biliary Tree.- Bile Duct Function in Biliary Secretion.- Kinetics of Hepatic Uptake and Excretion of Organic Anions.- Session 3 Bilirubin Conjugates.- Bilirubin Conjugates in Bile.- Comparative Studies on the Structures of Conjugated Bilirubin-IX? and Changes in Cholestasis.- Session 4A Bile Acids and Lipids I.- Some New Aspects of the Regulation of Cholesterol Biosynthesis and Metabolism of Mevalonate.- Bile Acid Metabolism and its Control.- Diurnal Variation in Bile Acid Biosynthesis.- Hepatic Transport of Bile Acids.- Formation, Metabolism and Excretion of Bile Salt Sulfates in Man.- The Alio Bile Acids.- Dissolution of Gallstones by Chenodeoxycholic Acid.- Session 4B Bile Acids and Lipids II.- The Enterohepatic Circulation of Bile Acids in Man.- Bile Phospholipids: Origin and Function.- Biliary Lipids in Pregnancy.- Session 5 Cholestasis.- Intrahepatic Cholestasis.- Molecular Pathology of Cholestasis.- List of Participants.- Appendix I. Recommendations on Bile Salt Nomenclature.- Index of Speakers and Participants in Discussions.