Biologists have found that neural-crest stem cells--multipotent, migratory cells unique to vertebrates that give rise to facial bones, smooth muscle, and other structures -- also play a key role in building the nose's olfactory sensory neurons, the only neurons that regenerate throughout adult life. Learning how they form may offer insights into how neurons in general can be induced to differentiate or regenerate and new avenues for the treatment of neurological disorders or injury.