(A) In the spinal cord, the NSCs located in the ventricular zone (VZ) transition fate from neurogenesis to gliogenesis in a process called the gliogenic switch. (B) Upon specification, astrocyte progenitor emerge from the VZ into the intermediate zone (IZ). Waves of proliferation from astrocyte precursors (ASPs) have been reported but this ability decreases as development progresses (20). A similar observation was reported in the cortex, although the timing is different (13). At the same time, ASPs migrate into the mantle zone (MZ) to reach their final location. While the mechanisms that regulate this process remain relatively unknown, it has been suggested that astrocytes have limited migratory capabilities (31). (C) Finally, astrocytes become mature and functional during the post natal stages of development.