Analysis of research literature shows both important commonalities and differences between how children learn to read and how adults can be taught to read in literacy programs. Both the narrow and broad definitions of literacy are legitimate for specific purposes. The narrow definition identifies literacy acquisition with learning how the writing system works, whereas the broader definition refers to the functional contexts of basic literacy. Learning to read English requires mapping meaningless speech units to meaningless writing system units. Development of reading skills rests on phonological and orthographic components. Some phonological knowledge assists learning how to read, whereas practice at reading strengthens the orthographic-phonological representations of words that are critical in fluent reading. Comprehension is a critical part of reading from the very beginning, although it is largely a general language ability rather than a reading-specific one. Low-literate adults experience the same phonological and lexical failures as children who have difficulty learning to read. Several studies point to adult problems in lexical and phonological processing, and some suggest successful training in phonological awareness. For low-literate adults who show sufficient basic literacy skill, instruction should focus on reading practice. Beyond obvious differences in age and experience, low-literate adults and beginning readers differ in goals and motivations. (Contains 123 references.) (YLB)