Spatial and temporal coordination of the numerous interactions between cells and their environment is critical for regulation of cellular behavior and homeostasis. Cells must interact with and respond to neighboring cells, the surrounding extracellular matrix, soluble factors, and other physical forces. Cells integrate the various signals that are transduced from their microenvironment and respond to it by remodeling their cytoskeleton, a highly dynamic complex network of protein filaments that reorganizes continuously to enable changes of cell shape and movement. From bacteria searching for nutrients to neurons searching for synaptic partners, at some point in their life cycle most cells must remodel their cytoskeleton in order to change their shape and/or move.