Plasma albumin is an important protein in the human body and is responsible for transport and binding of many molecules. Furthermore, it is involved in mediating blood volume and colloid osmotic pressure (COP). As hypoalbuminemia occurs, as is the case in a number of clinical disorders, adaptation mechanisms may be involved. Serum albumin concentration is the net result of physiological processes like synthesis and catabolism. Measurement of one of these processes can provide therefore a more dynamic insight into the adaptation mechanism of albumin metabolism in relation to an underlying disease than would be obtained by changes in albumin concentration alone. This review highlights several studies over the past years that have contributed to knowledge of albumin metabolism. A short introduction is given for synthesis, formation and catabolism of albumin, after which an overview is given on how to measure albumin turnover including a general approach. Finally, albumin metabolism focused on patients with renal diseases will be discussed.