A great nonfiction book proposal is the key to convincing an acquisition editor you deserve a substantial advance and getting your book published.
What should be included in a book proposal?
Concept:
A brief, no more than one page description about why your book is unique.
Market:
Who will buy your book and why. Include the demographics of your potential readers and how many of them there are. If you can, quote statistics, such as baseball is the most often viewed sport on TV with x million people watching. Or x number of people attend arts and crafts shows a year. Or $xxx dollars of revenues are generated by customers buying garden tools. Whatever is relevant to your books topic.
Competition:
Similar books that have been published in the last year or that will be coming out soon. You can get an idea of soon-to-be published books by going to amazon.com, and searching under key words. When you get a listing of books that you think are similar to yours, then rank by publication date.
Include the title, author, ISBN, and a brief description. Then state why your book is better or what your book addresses that the competition...