Editorial Services

I am currently closed to new editorial work. Follow me on Twitter for updates.

I offer freelance editing for middle grade, young adult, and adult fiction (no short stories, picture books, or nonfiction, please!). I pride myself on my attention to detail and structure alike, as well as my accessibility and friendliness. I will push you to make your materials the best they can be without encroaching on your vision.

Here’s some information about me, my career, and my editing style. For a more comprehensive overview, please see here.

  • I’ve worked in book publishing since 2015. I got my start as an editorial intern at Entangled Publishing, and I went on to intern and assist at five literary agencies, including Writers House, Stonesong, and Triada US. I currently work in sales at NetGalley.
  • Over the course of my career, I’ve had the pleasure of working with many New York Times and independent bestselling authors, as well as major award winners, nominees, and finalists (including the William C. Morris Award, Printz Award, National Book Award, Coretta Scott King Book Award, Boston Globe-Horn Book Award, and E.B. White Read-Aloud Award).
  • Authors I have worked with include #1 New York Times best sellers like Becky Albertalli (author of Simon vs. the Homo Sapiens Agenda, adapted into the film Love, Simon, as well as Kate in Waiting and Imogen, Obviously, among others); major award-winners like Varian Johnson (author of The Parker Inheritance, The Great Greene Heist, and many more); critical darlings like J. Elle (author of Wings of Ebony, Ashes of Gold, A Taste of Magic, and more); Ryan La Sala (author of Reverie, Be Dazzled, The Honeys, and Beholder); Jessica Kim (author of Stand Up, Yumi Chung!, Make a Move, Sunny Park!, and On Thin Ice); Kelly Loy Gilbert (author of Conviction, Picture Us in the Light, and more); among many others.
  • Since its inception in 2016, I’ve volunteered with Beth Phelan’s #DVPit, as well as the nonprofit organization Diverse Voices, Inc. (2019 – 2023), offering free pitch, query letter, and manuscript critiques for marginalized writers. I also had the privilege of speaking with marginalized authors selected for DVI’s author mentorship program, serving as an industry panelist.
  • I’ve edited for many authors who have gone on to sign with literary agents and sell their books to publishers. Here are some kind things a few clients have had to say about my work.
  • I’m happy to work directly with writers, agents, editors, and any members of a book’s publishing team.

My editing style is hands-on, and I’m always thinking from two perspectives: an editor’s and a writer’s. As a writer myself, I know how frustrating vague, seemingly arbitrary feedback can be. That’s why I’ll never say, for example, “Cut this scene”—instead, I’ll explain exactly why this scene isn’t carrying its weight, how that affects the manuscript, and why I think it might be better if this scene were removed. I’m also always happy to answer your questions and help you brainstorm plans of attack for no extra cost. When you hire me, you won’t work with a distant, uninvolved editor; you’ll work with a publishing professional who’s on your team, ready, willing, and excited to help however he can.

My services, discounts, and contact form are below. Please do get in touch at hello AT markobrienedits DOT com if you have any questions. I can’t wait to work with you!


Query edit: $25 (one round; any additional rounds are $10)

I wrote dozens of query letters before signing with my agent, and I’ve read, discussed, and made decisions regarding countless others throughout my career. I know what works and what doesn’t. When you book me for a query letter edit, I’ll look at everything from structure and format to diction and punctuation. I offer a thorough critique, pointing out areas that need improvement and writing long strings of exclamation points when I love something. Most of all, I make sure every word counts—and shines.

Submission package: $50 (one round; any additional rounds are $25)

Most literary agents want sample pages included with your query letter, and it’s vital that these opening pages draw them in. When you book me for a submission package, I’ll help you ensure the first ten pages of your manuscript—formatted in Times New Roman, size 12, with one-inch page margins all around—and your query letter are the best they can be.

Editorial letter: $0.005/word ($50 per 10,000 words)

Drawing upon my five years of experience writing these for agents and editors, I’ll review your full manuscript and write an editorial letter (two pages minimum, usually more) when you book me for this service. If you’re only concerned about big-picture elements like pacing, character, and plot, this is the option for you! My edit letter will break down what works in your manuscript and how to make it even better, in addition to what needs fixing. I always offer suggestions, too!

Full manuscript line edit: $0.007/word ($70 per 10,000 words)

I don’t like to brag, but I will: many of my clients and bosses alike have praised me for my attention to detail in particular. When you book me for a full manuscript line edit, I’ll review your entire manuscript, leaving suggestions, questions, and hearts in track changes. After noting every problem area I find on a line-level scale and suggesting how to fix them, I’ll ensure you walk away happy with your manuscript.

Full manuscript developmental and line edit: $0.01/word ($100 per 10,000 words)

Selecting this package gives you the same experience as booking me for an editorial letter and a line edit, all for a discounted price—and I’ll throw in two rounds of edits on your query for no extra charge! When you book me for this service, I’ll review your full manuscript with an eye for the big-picture problem areas, which I’ll compile in a comprehensive edit letter and send to you. You’ll send back your edited manuscript, and I’ll leave notes in track changes concerning those nitty-gritty details.


I offer free submission package edits for Black writers, and yes, this absolutely includes biracial and multiracial Black writers. There are no strings attached to this offer, and it does not expire. Please allow about two to three weeks, depending on my workload, for me to read and send you my notes.

I also offer 20% off the total cost of any editorial service for marginalized writers, using the definition of diversity found on the We Need Diverse Books website. This includes but is not limited to queer (including asexual, aromantic, trans, non-binary, and questioning, of course) writers, Black writers, Indigenous writers, writers of color, disabled writers, and writers who belong to ethnic, cultural, and religious minorities. I go by the honor system; you’re free to disclose your marginalization(s) to me if you wish, but I don’t require it, and I will not ask.


Please submit your information through the form below, or email me at hello AT markobrienedits DOT com.

Please be sure to include your manuscript’s word count, a quick summary (this can be informal), what you’re looking for, and whether any discounts are applicable to you. Again, you don’t need to disclose any specific marginalizations—you could simply say, for example, “I’d like to take advantage of the 20% discount for marginalized writers.”

Please note: I cannot guarantee you will sign with an agent or be offered a contract with a publishing house after working with me.