In American colleges and universities, plagiarism is a hot topic: teachers wail and moan about the rise in student plagiarism (though often without evidence to demonstrate this supposed rise); they complain that the Web has "caused" plagiarism; and at the same time, many believe that technology is the key to "solving" the problem of student plagiarism through the use of services like turnitin.com. Plagiarism is generally defined as the use or appropriation of other people's text or ideas in one's own writing without citation of the original source; it is commonly treated as synonymous with cheating or "stealing," hence the moral dimension ascribed to it. Examples of student plagiarism seem to abound: ask virtually any teacher in any discipline, and he or she will describe experiences with students' turning in work that is "not their own." This phenomenon runs the gamut from students' patchwriting, or interspersing their own writing with phrases, sentences, or paragraphs from a classroom text, one the teacher can be assumed to know well; to students' badly paraphrasing sources not shared in the classroom, such as textbooks from other classes, an encyclopedia, or other print or online source (usually with an inadequate attempt at citation); to a student's turning in a paper written entirely by someone else, either a friend who took the same class or someone whose work has been purchased or downloaded from the Web. Clearly, even the word "plagiarism" itself is being asked to describe many disparate phenomena. Unfortunately, despite their outrage, or perhaps blinded by it, many faculty have not endeavored to recognize and acknowledge the many subtleties and complications embedded in something so seemingly transparent as the appropriation and citation of text, practices which are often taught as essentially punctuation exercises. Libraries serve the entire school, and as such, librarians are accustomed to helping students with papers and problems in any number of disciplines. Librarians have a breadth of knowledge--and knowledge of source materials--in a variety of fields, as well as an appreciation for the range of conventions governing the appropriation and documentation of text across disciplines, that many faculty do not possess. This breadth allows librarians to take multiple perspectives on plagiarism and citation practices. In this article, the author discusses the role of librarians and writing centers in addressing citation practices and plagiarism. (Contains 7 footnotes.)