The ability of lentivirus vectors to stably transduce postmitotic cells by genomic integration and early evidence of a capacity for retrograde axoplasmic transport, depending on the envelope pseudotype, underpin the immense potential of this vector system for neuronal transduction (1 –3 ). The bulk of studies performed to date have focused on central nervous system (CNS) neurons despite the relative merits of peripheral nervous system (PNS) neurons as targets for gene transfer (4 –6 ). The neural circuitry of the PNS is relatively simple, accessible, and anatomically discrete. Dorsal root ganglion (DRG) sensory neurons exemplify these properties, are readily cultured ex vivo after dissociation or as intact DRG explants, and as a consequence, have been extensively exploited as a model system by neurobiologists (7 ). The demonstrated ability of human immunodeficiency virus type 1 (HIV-1)-derived lentivirus vectors to stably transduce DRG sensory neurons (8 ) extends the utility of this model system for both basic science investigations of neuronal structure and function and for the development and evaluation of gene therapy strategies targeting PNS neuropathology.