The overview gives an agent or editor a quick glance at the nonfiction project as a whole. It should be a one- to two-page synopsis, written in narrative form, that gives a clear view of the purpose and need for your book. An agent will use the overview to help market your book to publishers; an editor will use it as an internal sales pitch when he thinks a project deserves a contract offer.
The lead paragraph of your overview is the “hook.” This is where you explain why readers (and publishers) will be interested in your book. If you're writing an inspirational book on living with diabetes, for example, you might lead with statistics on how many American adults develop diabetes. You also could point out that, while there are countless cookbooks and health manuals aimed at diabetics, there is a shortage of material that focuses on positive anecdotes and inspirational tales of people living with the disease.
If your project is, or could be, part of a series, mention that in your lead, too. More and more agents and publishers these days are looking for multiple-book deals rather than so-called one-shotters. This makes sense from a business standpoint; successful agents want authors who are interested in building careers, and publishing houses are interested in landing potentially successful series that can generate ongoing profits.
The pitch is a brief statement (one or two sentences at most) that tells the agent or editor what your book is about. You should be able to adapt a sentence or two from your query letter to include here. Think of it as a blurb on a book jacket: a clear, concise statement of the overall concept of your book.
After you've offered the pitch, you can elaborate further on the book's contents, but don't get tangled up in too much detail. Your overview should be lively and engaging, leaving the agent or editor with a clear understanding of what your book covers, the point of view it offers, and so on. If your project includes research or interviews with prominent experts, include that in your overview.
Finally, let the agent or editor know an approximate word count for your project. Most nonfiction books are a minimum of 60,000 words, but this is just an offer. An editor may later ask for a different length if your project is accepted.
Literary agencies and publishers often have their own guidelines for formatting various elements of a book proposal, including the outline. If such guidelines are available, follow them. If there are no guidelines, or if the guidelines are silent on formatting, the format offered here will serve you well.
Your overview should be no more than two pages, and, in most cases, one will suffice. The title of your book is always uppercase. On first reference, use the full title and subtitle of your book; on second reference, you can use just the main title if appropriate. For example, if the working title of your book is
The overview should be single-spaced, with an extra line between paragraphs. Do not indent paragraphs when using this format.
Here's how an overview for this book might read:
You've just come up with a killer idea for the Great American Book, and you can't wait to see it on the shelves of your local Barnes & Noble Booksellers. But how do you get there from here?
Note that this sample overview is just four paragraphs, including the proposed word count. But it tells agents and editors everything they need to know about the book idea, including the main points the book will cover and how the information is presented. Ideally, an agent or editor should be able to tell from this one page whether your book idea fits into her line, whom the target audience is, and what is new or different about your idea.