This paper describes four syndromes of acquired dyslexia (that is, reading deficits in previously literate adults who have suffered neurological damage): deep dyslexia, surface dyslexia, phonological dyslexia and letter-by-letter reading. The format of the description inquires whether reading performance in each syndrome is (1) sensitive to dimensions of words (such as word length or part of speech), (2) affected by experimental manipulations (such as exposure duration), and (3) relevant to theoretical issues (such as the nature of codes for word recognition in reading). The four patterns of reading impairment seem to relate in an orderly way to these dimensions, manipulations and issues drawn from the literature on normal word recognition and production. Such orderly relationships, it is claimed, favour the position that neuropsychological observations are germane to conceptions of normal reading.