This 3-volume encyclopedia covers all aspects of synthetic membranes at the fundamental as well as practical levels. Furthermore, this reference offers the opportunity to critically assess the status of advancements in the materials science of membranes and their engineering applications. This first volume focuses on the basic principles and properties of membranes, the primary separation mechanisms, and classification of membranes. Other topics include common metrics for membrane performance (permeability, molecular weight cutoff, and rejection/retention); typical difficulties such as concentration polarization; membrane fouling along with currently practiced; and emerging solutions.