Somatic sensory neurons have two target areas, one in the peripheral end organ and the other within the central nervous system. For many decades, it was thought that only the peripheral target was important for the survival of developing and mature sensory neurons. Nerve growth factor (NGF), which is required for the survival of embryonic sensory neurons in vitro, was thought to provide peripherally derived trophic support only during development and that mature sensory neurons were insensitive to NGF. In this article we review recent evidence which demonstrates a broader role for NGF and for the central target in the maintenance of sensory neurons. We review the biology of NGF in relationship to the life history of sensory neurons, the potential use of NGF as a pharmacological agent to ameliorate the effects of injury, and new data establishing the central target tissue as a source of neurotrophic support.