How Actin Assembly Is Modulated at Filament Barbed Ends in Motile Processes -- Proteins of the Actin Depolymerizing Factor/Cofilin Family -- Profilin, an Essential Control Element for Actin Polymerization -- Srv2/Cyclase-Associated Protein (CAP) -- Twinfilin Family of Actin Monomer-Binding Proteins -- Intracellular ?-Thymosins -- Multirepeat ?-Thymosins -- Wasp and WAVE Family Proteins -- The Verprolins as Regulators of Actin Dynamics -- A Common Binding Site for Actin-Binding Proteins on the Actin Surface. The actin cytoskeleton plays a central role in many cellular processes including cell motility, cytokinesis, endocytosis and phagocytosis. The structure and dynamics of the actin cytoskeleton is regulated by a large number of proteins that interact with monomeric and/or filamentous actin. Actin monomer binding proteins provides a comprehensive view on actin monomer-binding proteins and the mechanisms by which they contribute to actin dynamics and various actin-dependent cellular processes. This new title contains chapters that describe the basic mechanisms of actin dynamics as well as the structural principles by which various actin-binding proteins interact with actin.