One area of writing that may be particularly problematic for less skilled writers and writers with learning disabilities is constructing well-formed sentences. In this single-subject design study, sentence-combining practice with a peer-assistance component was used to improve the writing ability of 6 fourth-grade students with and without learning disabilities. The results support the use of sentence-combining practice to increase sentence construction ability. Furthermore, sentence-combining instruction led to gains in story quality and writing complexity. (Contains 5 figures.)