Two experiments studied the acquisition and transfer of text-editing skill. The first experiment, originally reported in Singley and Anderson (1985) but reanalyzed in greater detail here, found nearly total transfer between two similar line editors and partial transfer from the line editors to a screen editor. Analyses of the keystroke data revealed that the majority of the improvement during both learning and transfer was concentrated in the planning components of the skill. The second experiment found little evidence for negative transfer between a pair of screen editors designed for maximal interference using a classic interference paradigm. The few instances of negative transfer observed were better characterized as the positive transfer of nonoptimal methods rather than instances of true procedural interference. These results support an identical elements model of transfer based on a production system representation of cognitive skill. The relative magnitudes of transfer observed were consistent with detailed measures of production system overlap. In addition, localized transfer sites were hypothesized and identified through a series of microanalyses. Finally, specific transfer predictions based on the differential practice of general and specific components were tested and confirmed.