(Figure Presented) DNA burns its bridges: A unidirectional molecular motor that moves an oligonucleotide cargo along a self-assembled track is powered by restriction endonuclease hydrolysis of the phosphodiester backbone (see scheme). Damage caused to the track by the restriction enzyme prevents the cargo from stepping backwards and therefore imposes directionality. © 2005 Wiley-VCH Verlag GmbH and Co. KGaA.