Prisca Martens's most powerful teacher has been her daughter Sarah. When Sarah at age four responded "I already know how to read" to the suggestion that this was something she would learn in kindergarten, Martens realized children's perceptions of literacy and of themselves as learners may differ from those of adults. Over the three years Martens observed and analyzed Sarah's reading and writing (ages two through five), Sarah helped Martens rethink her notions about literacy: what literacy is, how children learn literacy, and as Sarah entered kindergarten, what teachers can do to support and facilitate that learning in school. In "I Already Know How to Read" Martens documents how Sarah, through meaningful literacy experiences in her social community, understood literacy and invented reading and writing for herself. Numerous reading and writing samples, organized around broad research questions, present Sarah as an inquirer who actively constructs her understanding of literacy and ways to be literate. Martens recognizes that children's opportunities and experiences with print differ. But by looking closely at one child's literacy development, we learn how to see and understand the literacy development of others. The implications for the classroom are extraordinary-as Sarah taught her mother to see, her story will help practicing and preservice teachers to see as well.