There is a language to proofreading; a series of squiggles and signs that indicate errors. And finding errors is the only function of proofreading. The problem with such a code, as with any language, is that both parties have to understand its meaning, and few do, especially outside of the publishing business. I have yet to meet a student who knows it. Moreover, most of the writing I receive to work on contains problems in a number of areas, not just a final tidy-up and check for glitches. Therefore, what I mean by proofreading is that final edit, the polish that comes after all the other problems are fixed. However, I work on the various problems in a text as part of the editing process, and proofreading is buried in that process, so typos, grammar errors etc are removed immediately rather than remedially. The result is usually a lot of red ink and sometimes a disheartened client, but the task of editing and proofreading is condensed and therefore more efficient and cost effective. So get ready to see red ink all over your hard work but understand the benefits to your text and your bank account.