The knowledge of letter names measured just before children enter school has been known for a long time as one of the best longitudinal predictors of learning to read in an alphabetic writing system. After a period during which the comprehensive investigation of this relationship was largely disregarded, there is now a growing interest in attempts to understand the role(s) letter names play in literacy acquisition. This paper reviews these recent studies and emphasizes their main findings regarding the influence of letter-name knowledge in early and formal literacy for three main components of literacy acquisition: first, the emergence of the phonological processing of print; then, the learning of letter-sound correspondences; finally, the development of phonemic sensitivity skills. The final section discusses the status of letter-name knowledge (LNK) in literacy acquisition and suggests possible directions for further research.