This historical review of the literature addresses the relationship between spoken and written language with respect to: (1) comparison and contrast of features; (2) the instructional program; and (3) the contributions of research. The review includes direct quotations of researchers in describing the studies to preserve each researcher's personal interpretation of the individual investigation. It concludes that the relationship between oral and written language through an examination of similarities and differences and the search for the most effective teaching approaches to accommodate each of the language modes would continue as a major focus in language arts instruction. The purpose of the historical review is to provide a wide perspective to the changing pace, content, and style of instruction and practice. (Contains a 47-item bibliography of research published between 1925 and 1969.) (NKA)