This study investigated knowledge of letter names and letter sounds, their learning, and their contributions to word recognition. Of 123 preschoolers examined on letter knowledge, 65 underwent training on both letter names and letter sounds in a counterbalanced order. Prior to training, children were more advanced in associating letters with their names than with their sounds and could provide the sound of a letter only if they could name it. However, children learned more easily to associate letters with sounds than with names. Training just on names improved performance on sounds, but the sounds produced were extended (CV) rather than phonemic. Learning sounds facilitated later learning of the same letters' names, but not vice versa. Training either on names or on sounds improved word recognition and explanation of printed words. Results are discussed with reference to cognitive and societal factors affecting letter knowledge acquisition, features of the Hebrew alphabet and orthography, and educational implications.