The authors tested theoretically driven predictions as to the ways in which syntactic awareness, or awareness of word order within sentences, might contribute to reading comprehension, the end goal of reading development and instruction. They conducted a longitudinal study of 100 English-speaking children followed from Grade 3 to 4. Children completed measures of syntactic awareness, word reading, reading comprehension, and reading-related control variables. Path analyses at each of Grades 3 and 4 show a unique concurrent relation of syntactic awareness with reading comprehension, but not to word reading skills. Longitudinal analyses reveal that syntactic awareness at Grade 3 predicts gains in reading comprehension between Grades 3 and 4. Together, findings suggest a robust role for syntactic awareness in the development of reading comprehension.