Thin-film electrets have been patterned with trapped charge with submicrometer resolution using a flexible, electrically conductive electrode. A poly(dimethylsiloxane) stamp, patterned in bas-relief and supporting an 80-nanometer-thick gold film, is brought into contact with an 80-nanometer-thick film of poly(methylmethacrylate) supported on n-doped silicon. A voltage pulse between the gold film and the silicon transfers charge at the contact areas between the gold and the polymer electret. Areas as large as 1 square centimeter were patterned with trapped charges at a resolution better than 150 nanometers in Less than 20 seconds, This process provides a new method for patterning; it suggests possible methods for high-density, charge-based data storage and for high-resolution charge-based printing.