This book provides a comprehensive overview of the basic principles, concepts, techniques and latest advances in the field of biomembranes and membrane-associated processes. With new emerging technologies and bioinformatics tools, this is a promising area for future study and research. The book discusses the composition, fluidity and dynamic nature of phospholipid bilayers, which vary with cell/organelle type and function. It describes the various types of transport proteins that facilitate the transport of polar and nonpolar molecules across the membrane actively or passively via ion-channels or through porins. It also explores the many cellular functions membranes participate in: (1) energy transduction, which includes the electron transport chain in inner membrane of mitochondria and bacterial cytoplasmic membrane and photosynthetic electron transport in thylakoid membranes in chloroplast and photosynthetic bacterial membranes; (2) cell-cell communication involving various signal transduction pathways triggered by activated membrane receptors; (3) cell-cell interactions involving various types of adhesion and receptor proteins; (4) nerve transmission involving opening and closing of voltage gated ionic channels; and (5) intracellular transport involving the processes of endocytosis, exocytosis, vesicular transport of solutes between intracellular compartments, membrane fusion and membrane biogenesis.