Fluent readers can read connected text with accuracy, automaticity, and prosody. Without practice, automaticity cannot develop in reading, and readers must focus their attention on decoding, limiting their ability to simultaneously comprehend. Researchers have traditionally assumed that fluency and comprehension have a unidirectional relationship whereby fluency affects comprehension. However, a recent study by Klauda and Guthrie suggests that the relationship between fluency and comprehension may be reciprocal over time; that is, comprehension may also predict fluency. In the present study we examine this reciprocal relationship using structural equation modeling. We test various models that measure the relationship between fluency and comprehension over 3 time points spanning an academic year. The results indicate that compared to the traditional model in which fluency predicts concurrent comprehension, models exhibiting a reciprocal relationship do not fit the data better. We discuss the implications of these results.