The neural crest produces both neuronal and nonneuronal derivatives in response to a variety of environmental cues. Here, we have analyzed the effects of retinoic acid on the differentiative behavior of quail trunk neural crest cells in vitro. We show that retinoic acid selectively increases neurogenesis in cultured neural crest cell populations, probably by promoting the survival and stimulating the proliferation of neuronal precursors. Our results suggest that neural crest-derived neurogenic precursors are specific targets for retinoic acid in vitro and raise the possibility that retinoic acid promotes the generation of peripheral neurons in vivo.