Purpose: This article addresses sentence comprehension as a requirement of reading comprehension within the framework of the narrow view of reading that was advocated in the prologue to this forum. The focus is on the comprehension requirements of complex sentences, which are characteristic of school texts. Method: Topics included in this discussion are (a) evidence linking sentence comprehension and syntax with reading, (b) syntactic properties of sentences that make them difficult to understand, (c) clinical applications for the assessment of sentence comprehension as it relates to reading, and (d) evidence and methods for addressing sentence complexity in treatment. Conclusion: Sentence complexity can create comprehension problems for struggling readers. The contribution of sentence comprehension to successful reading has been overlooked in models that emphasize domain-general comprehension strategies at the text level. The author calls for the evaluation of sentence comprehension within the context of content domains where complex sentences are found.