Writers have to forearm themselves: You need to know what range of tasks acquisition editors do writing the perfect query letter for fiction and nonfiction books. You also must understand the questions acquisition editors have to answer at publishers' editorial board meetings. Knowing all this enables you to convey the info they require to pitch your book to the board. It's the same for nonfiction, but your proposal has to go a step further and provide more detail for acquisition editors.
Both the query and the proposal, if you cover the bases, also reassures the editor that you're a professional too.
In a previous post, I did my best to convince you of the value of hiring a freelance editor to take a dispassionate look at your manuscript to show you what’s possible and help you gain perspective on your work. I argued that taking this step might make the difference between having your manuscript looked at by a publisher or tossed into the slush pile. Here, I’m going to tell you what an acquisitions editor does—and if this doesn’t convince you, then perhaps nothing will. in two main ways:
1) By choosing manuscripts received from agents or authors that have excellent commercial promise
2) By seeking out authors to write specific projects that the publishing house has determined will sell.
Both jobs fall to the acquisitions editor. She is the first to see a manuscript, and if she doesn’t like it—really like it—it will go no further. But she must do more than just like it. She must convince her superiors—the publisher as well as the marketing and publicity departments—to really like it as well. She must pitch it down to the last detail: the superior quality of the writing; the manuscript’s uniqueness and slant; its suitability for the publisher’s booklist; its favourable comparison to other titles in the market; the cost to produce; timing of publication; price; expected profit; longevity. She must also assess the author: How well known is s/he? How many titles has he published? What are his sales? How much marketing experience does she have? Is she cooperative or a pain in the ass? Does he “show” well at media events and book signings, or does he look like he’d rather be hiding in the weeds?
The acquisitions editor’s job is riding on all of this. If the titles and authors she promotes do not end up making money for the publishing house, she’s gone. So, this is not really about you, the writer; it’s about her! If you want to impress her, do everything you can to produce the best you can; and, please, check the publisher’s submissions guidelines and be prepared to wait some time while the acquisitions editor pitches your book to the publishing house.