I have experience with just about any kind of editing (except math). This includes fiction and nonfiction books, academic papers, scholarly articles, grant proposals, resume's, immigration documents, college applications, and business writing. A lot of my clients are professionals or academics whose first language is not English. They appreciate how well I can smooth out the awkwardness in their writing.
I've also taught and tutored writers from middle school to graduate school, and I've helped students prepare for SAT and similar writing tests. With six years' experience at a drop-in writing center, I've gotten good at quickly seeing where students or writers need help, and meeting them there.