Résumé : We examined the hypothesis that formal education and literacy impact the richness and precision of semantic knowledge but not the organization of semantic categories and basic mechanisms of access to them.In Experiment 1, adults of varying levels of formal education were presented with semantic fluency tests and a superordinate naming task. Experiment 2 examined the impact of reading proficiency on adults of varying degrees of literacy. They were presented with simple semantic, alternating semantic and phonemic fluency tasks, as well as with literacy-related, reasoning and memory tests.Fluency was analyzed in terms of overall performance, sequential order and speed of responses. Despite lower performance, illiterates and adults with null or limited formal education displayed taxonomic clustering and retrieval by semantic subcategory, as did participants with higher formal education levels. Yet, formal education and literacy slightly speed up access to categories, probably providing useful cues for generating category exemplars.