During development, cells must migrate from their origin to their final destination, a process that is dependent on the actin cytoskeleton. Cells can migrate independently or cohesively as a unit, in a process known as collective cell migration. In migrating cells, the actin cytoskeleton facilitates migration through the extension of actin-based protrusions, promoting adherence to the extracellular environment, and the retraction of trailing portions of cells. The regulation of these actin-based cellular mechanisms has been heavily studied in populations of individually migrating cells, mostly in in vitro contexts. However, how these processes are regulated and coordinated during collective cell migration in vivo remains largely unknown.