Illiterate, unschooled adults were tested on their notions of word length. Experiment 1 showed that only about half of them performed very poorly on a task requiring the production of a long/short word. They were clearly inferior to formerly illiterate, unschooled adults. The illiterate group also broke up neatly into two subgroups, one performing perfectly or very well, the other failing completely or almost completely, when required to match the written and the oral form of long/short words. Similarly, Experiment 2 showed that about half of the illiterates were unable to choose the longest of two names when presented with drawings of objects. The results suggest that learning to read, though not strictly necessary, plays a decisive role in the development of the ability of many individuals to focus on phonological length.