This report contains three papers discussing skill hierarchy approaches to reading instruction. Jana Mason presents an historical and theoretical review of the notion of a reading skills hierarchy, relates it to three major types of reading programs currently in use, and argues that it is instructionally advantageous to construct a decoding hierarchy but not a comprehension skills hierarchy. Jean Osborn summarizes the programming, instructional, and teaching strategies used for the presentation of decoding skills in four published reading series, and points out that, although each program does teach a set of decoding skills, programs differ in the skills taught and the order and rate at which they are introduced. Barak Rosenshine explores what is known about skill hierarchies in reading comprehension, identifying major reading comprehension skills but finding no evidence of a skills hierarchy in elementary reading series. (AA)