Little is known about the architecture of cellular microenvironments that support stem and precursor cells during tissue development. Although adult stem cell niches are organized by specialized supporting cells, in the developing cerebral cortex, neural stem/precursor cells reside in a neurogenic niche lacking distinct supporting cells. Here, we find that neural precursors themselves comprise the niche and regulate their own development. Precursor-precursor contact regulates b-catenin signaling and cell fate. In vivo knockdown of N-cadherin reduces b-catenin signaling, migration from the niche, and neuronal differentiation in vivo. N-cadherin engagement activates b-catenin signaling via Akt, suggesting a mechanism through which cells in tissues can regulate their development. These results suggest that neural precursor cell interactions can generate a self-supportive niche to regulate their own number. Highlights - Cortical ventricular zone neural precursors exhibit b-catenin signaling N-cadherin maintains b-catenin signaling in cortical precursors N-cadherin regulates neuronal differentiation and cell cycle exit via b-catenin N-cadherin signals through Akt and phosphor-Ser552 of b-catenin