Charge traps in pentacene thin-film transistors (Figure, left) have been imaged using electric force microscopy. The Figure shows a map of the trap distribution just below (middle) and well above (right) the transistor threshold voltage. It is found that the long-lived charge traps in polycrystalline pentacene are distributed inhomogeneously and do not appear to be associated with grain boundaries, as is generally assumed (see cover).