Simple and efficient gene transfer to the skin would facilitate many local and systemic gene therapy applications. Here we report a novel approach that allows installation and expression of plasmid DNA without a particulate carrier into the skin for the purposes of gene therapy. A device with a constantly high-frequency oscillating bundle of fine metal needles allows puncturing of the skin and leads to DNA transfer to skin-associated cells and expression of reporter genes in mice. Furthermore, puncture-mediated instillation of an expression vector coding for a single T cell epitope induces specific cellular immune responses. If this approach could be optimized, puncture-mediated gene transfer might be useful for the treatment of large body areas with plasmid DNA for the purpose of somatic gene therapy.