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Olfactory neurogenesis occurs continuously throughout the lives of vertebrates, including in humans, and relies on the rapid, unceasing differentiation and integration of neurons into a complex multicellular network. The system-wide regulation of this intricate choreography is poorly understood; in particular, it is unclear how progenitor cells convert stochastic fluctuations in cell-cell signaling, over both space and time, into streamlined fate decisions. Here, we track single-cell level multicellular dynamics in the developing zebrafish olfactory epithelium, perturb signaling pathways with temporal specificity, and find that the continuous generation of neurons is driven by the spatially-restricted self-assembly of transient groups of progenitor cells, i.e. cellular neighborhoods. Stochastic modeling and validation of the underlying genetic circuit reveals that neighborhood self-assembly is driven by a tightly regulated bistable toggle switch between Notch signaling and the transcription factor Insulinoma-associated 1a that is responsive to inter-organ retinoic acid signaling. Newly differentiating neurons emerge from neighborhoods and, in response to brain-derived neurotrophic factor signaling, migrate across the olfactory epithelium to take up residence as apically-located, mature sensory neurons. After developmental olfactory neurogenesis is complete, inducing injury results in a robust expansion of neighborhoods, followed by neuroregeneration. Taken together, these findings provide new insights into how stochastic signaling networks spatially pattern and regulate a delicate balance between progenitors and their neuronal derivatives to drive sustained neurogenesis during both development and regeneration.