Two hypotheses concerning the development of skill at identifying typographically transformed words were tested. One claim is that a general skill independent of specific training instances is involved, and the other is that skill is based on memory for the analysis of specific instances encountered during training. Contrary to the general skill view, a series of experiments demonstrated that transfer of word identification skill was highly specific and occurred only when training and test instances shared common letters printed in the same case (i.e., uppercase or lowercase). Transfer of skill also depended on the visual patterns formed by adjacent letters and word shape. Presentation of a word in training and test phases significantly improved test phase identification of that word even when a unique visual pattern was used. These results are compatible with an instance-based view of word identification skill in which it is assumed that subjects develop skilled analysis of the visual and conceptual characteristics of specific words, and that this skill can be used to identify repeatedly presented words as well as predictable sets of novel words.