This chapter begins with an overview of the relevant characteristics of alphabetic orthographies, noting those that are known to influence both skilled reading and its development. It presents theories of reading that include a cross-linguistic perspective. The chapter summarizes current understanding of the processes involved in skilled word reading in the light of variations in grapho-phonemic consistency and considers the available evidence regarding word-reading profiles of adults with developmental reading disorders. Skilled word reading involves recognizing words fluently in the service of extracting meaning from written language. Most of the preceding effects are moderated by orthographic consistency. A central issue in cross-linguistic research on reading development concerns the nature and timing of influences of orthographic consistency on reading behavior and its cognitive underpinnings. The growing consensus indicates that the foundations of literacy are universal across alphabetic orthographies.