A lipoprotein is a biochemical assembly that contains both proteins and lipids. Many enzymes, transporters, structural proteins, antigens, adhesins and toxins are lipoproteins. Examples include the high density (HDL) and low density (LDL) lipoproteins, the transmembrane proteins of the mitochondrion and the chloroplast, and bacterial lipoproteins. This book presents and reviews important data on lipoproteins such as their metabolism and relation to coronary artery disease (CAD), the study of the presence of LP-X in a wide number of liver and biliary tract diseases with cholestatic features, the role of lipoprotein abnormalities as risk factors for macroangiopathy in type 2 diabetes, and others.