Book Proposal vs. Partial

Are you talking about non-fiction or fiction?

For fiction, a proposal is typically the first three chapters/50 pages and the synopsis. (I discovered this when an agent requested a "proposal" of my novel a few years back. I asked if that meant he wanted the full ms. Um, not. Slightly embarrassing but hey, I learned a new word.)

Fiction authors don't write a proposal. They write a query letter, which can be akin to the back cover blurb on a book. Sometimes they are asked for a synopsis. These are both different entities from a partial. A partial means "a part of the story". Usually it means the first part, so the first three chapters, or the first 30 pages etc.

For non-fiction, often writers have proposals, what they plan on doing (as opposed to fiction authors who have already done what they've done), as well as a platform as to why they are the best to write the book they are writing. They may have to offer a chapter by chapter breakdown etc. If, I'd imagine, an agent requested a partial (though I'm not sure if it happens as often with non-fiction as often the book isn't finished before representation), then I would assume the partial would be the same, ie the first few chapters or first several pages.

Yup, fiction writers do queries and partial/full. Non-fiction writers do proposal. As far as I know, a proposal contains an outline (chapter by chapter), concept, sample chapters, author bio, etc.

A partial (for fiction) is generally X pages or chapters with a synopsis and bio.

Occasionally a fiction agent or publisher will still ask for an "outline" of a novel, which tends to flabbergast fiction writers. (I believe small mystery press Midnight Ink still asks for outlines plus synopses.) I've never had to do one, and don't really know what a standard novel outline looks like. Back in the Old Days, novelists often sold books, through their agents or directly, on the basis of a first chapter and an outline. Those days are long gone.

Nowadays with agents for fiction, it's a query package, which, depending on the agent, can be 1) query letter only; 2) query letter plus synopsis; 3) query letter plus synopsis plus sample pages; 4) query letter plus synopsis plus partial (usually first three chaps or first 50 pages).

A nonfiction proposal is also a package, but it's less all-over-the-map than query packages for fiction. One or more sample chapters are usually part of the package. The three nonfiction books I've published were ones where the publishers came to me and my writing partner because of our expertise, so I never had to write a proposal. But if you are going to be submitting a nonfiction book proposal to agents or publishers, I'm told you really need to read Michael Larsen's How to Write a Book Proposal or something similar. It's a rather specific and arcane art. And, unlike the situation with novels, where you are expected to have written the book before you start looking for an agent, having your full nonfiction manuscript written can be seen as a drawback!