Over the last few decades, an increasing number of developing countries have embarked upon the organization of nationwide literacy programs. Although the rationale behind those programs varies from country to country, it is generally expected that efforts to increase the literacy levels of adults will have positive consequences for both the learners and the nation as a whole.

It is worth noting, however, that until now empirical evidence which could support these expectations has remained extremely weak. By and large, adult literacy has been a neglected area in terms of data collection and research. In many countries it may even be difficult to find precise information about simple facts such as the number of adults enrolled in literacy classes, the number of instructors, or the number of literacy proficiency certificates which have been delivered. In most cases the illiteracy rate, which is an essential indicator for any plan of action in the field of literacy, is only a crude measure based on self reporting by household heads and on questionable assumptions about the equivalency between a given number of years of primary school attendance and a sufficient proficiency level in reading and writing. Only recently have certain governments started using literacy tests to assess, by direct measurement, the levels of literacy of their population, most often on the basis of a representative sample household survey (for example, Kenya, Nicaragua, and Zimbabwe).

When it comes to the effects of literacy, the lack of appropriate information is even more disturbing. There are several studies which demonstrate the positive effects of a given number of years of primary schooling on farmers’ productivity (Jamison and Lau, 1982).