New twists on existing approaches often seem obvious with hindsight. In the case of purified or naked DNA vaccines, one way several researchers have been approaching the delivery problem is to use live attenuated bacterial pathogens. Now, Grillot-Courvalin et al.1 have taken a different tack, using a nonpathogen (rather than an attenuated pathogen) genetically modified to enter cells and release plasmid DNA. Their approach may have certain safety advantages over other bacterial systems for delivering DNA vaccines.