In the developing CNS, postmitotic neurons exhibit dynamic changes in the mode, direction and rate of migration as they traverse different cortical layers, but the mechanisms underlying this process is largely unknown. Recent studies show that the changes in Ca2+ transient frequency play a central role in controlling the neuronal cell migration in a cortical layer-specific manner. In this article, we will first describe how granule cells migrate through different terrains of the developing cerebellar cortex. We will then present how such migration of granule cells is controlled by altering the Ca2+ transient frequency in their somata. Finally, we will discuss how the loss of Ca2+ transients triggers the completion of granule cell migration at their final destination.