A deep, developmental construct and definition of fluency, in which fluency and reading comprehension have a reciprocal relationship, is explicated and contrasted with superficial approaches to that construct. The historical development of fluency is outlined, along with conclusions of the U.S. National Reading Panel, to explore why fluency has moved from being "the neglected aspect of reading" to a popular topic in the field. A practical, developmental instructional program based largely on the theoretical framework and research findings of Linnea Ehri is delineated. The nine essential components of that program include building the graphophonic foundations for fluency; building and extending vocabulary and oral language skills; providing expert instruction and practice in the recognition of high-frequency vocabulary; teaching common word parts and spelling patterns; teaching, modeling, and providing practice in the application of a decoding strategy; using appropriate texts to coach strategic behaviors and to build reading speed; using repeated reading procedures as an intervention approach for struggling readers; extending growing fluency through wide independent reading; and monitoring fluency development through appropriate assessment procedures. The position is taken throughout that teaching, developing, and assessing fluency must always be done in the context of reading comprehension.