This paper positions the importance of frequency sensitivity in the development of orthographic knowledge throughout childhood and promotes learning to spell as a vehicle which may be used effectively to develop this sensitivity. It is suggested that orthographic knowledge is advanced via a process of "frequency sensitivity" to "patterns and sequences" and "rules and regularities" particular to English orthography and that the process of sensitivity to these coarse grain orthographic patterns is influenced by consistency in sound and by morphological knowledge (knowledge of morphemes; words or word parts that form the smallest unit of meaning in language). A model highlighting the increasing importance of orthography and morphology as reading and spelling development progresses is presented. Discussion of the importance of considering phonology, orthography and morphology throughout literacy development and the relative importance of each is discussed. Distinctions are drawn between the processes involved in children who are good readers and good spellers, children who are good readers and poor spellers, and children who are poor readers and poor spellers. This paper outlines how considering these interrelated and developmentally sensitive contributors to literacy development can contribute to the practice of educational professionals in promoting the development of literacy skills throughout childhood.