One of the most common and vital areas of coverage in second language (L2) writing instruction is writing from sources, that is, the process of reading source text material and transferring content from that reading to writing. Research as well as everyday practice in the classroom has long shown that working with source texts is one of the most challenging of all academic literacy activities for L2 writers. This is particularly true in the domain of paraphrasing, an important and yet complicated device for the treatment of source text material. While the procedures involved in paraphrasing source text material may appear simple, the enactment of those procedures is a complex and often elusive experience for L2 writers. In this article we discuss a study of two mainland Chinese students' engagement with paraphrasing in an undergraduate academic writing course, with a particular focus on their understanding of the purposes and functions of paraphrasing and how such understanding influenced their paraphrasing practices. Our results reveal a multilayered relationship between the students and paraphrasing and contribute to the paraphrasing literature by drawing greater attention to paraphrasing from students' perspectives. (Contains 1 table.)