Our somatosensory nervous system enables people to gauge their relationship to the world around them. Thanks to the messages it carries, we feel sensations such as temperature, pressure, heat, and pain. It is the key not only to our physical interactions, but also to our social ones. Much about how the somatosensory nervous system develops remains mysterious, however. We know that the sensory neurons of this system emerge from a pool of neural crest progenitor cells that migrate during embryonic development and coalesce into dorsal root ganglia—nerve clusters on the left and right side of each vertebrae along the spinal cord. Ultimately, axons from these sensory neurons will infiltrate virtually every part of the body and help us sense the world around us. A key question that remains unanswered is which factors control the development of specific sensory neuron types. It has long been assumed that developing sensory neurons are pre-programmed from the start, butEli Zunder, an assistant professor of biomedical engineering, is among those challenging this assumption.