Summary.The aim of this study was to analyse data from a longitudinal study of a sample of culturally disadvantaged children and a matched control group to see what features distinguished a group of poor readers at age 7.5 years who remained seriously backward in reading throughout their school careers (Long Term Backward Group) from a group of equally low scoring readers of the same age who subsequently made relatively good progress in reading (Slow Starter Group). A discriminant function analysis was carried out using a selection of performance and behavioural measures obtained between ages 6 and 7 years, together with a global measure of the cultural and material provision in the children's home backgrounds. A combination of five of the seven measures produced a discriminant function which successfully distinguished 21 out of the 24 cases (87 per cent) in terms of their group membership. Although both groups obtained very low reading scores at 7.5 years, case records showed a marked difference between them in their pattern of progress through their infant school reading schemes. The findings supported a multi‐factorial explanation of long term reading failure in which a paucity of literary experience in the home and a limited oral vocabulary resulting in a low interest in and concentration upon pre‐reading and reading tasks in school, with associated behavioural problems, are salient featu