The next section in a nonfiction book proposal is Spin-offs. This also falls under the Introduction and includes Subsidiary Rights. This sections helps make you, the author, more enticing to the publisher by showing you have more to sell than one basic idea.
When you sell your book to a publishing house, the publisher acquires primary book rights. As Mike Larsen explains in How to Write a Book Proposal, primary rights include publishing the book hardcover, trade paperback, and/or as a mass-market paperback; book club rights; selling permission to excerpt part of within another work or second-serial rights to except the book or condense it or serialize the whole book in a periodical after publication; reproducing the text in other forms and media; reproducing the text in large-type or a royalty-free Braille edition; selling school editions; photocopying rights to all or part of the book for internal use by a school or business; selling the book through direct-response marketing channels; selling the book as a premium to businesses or nonprofits as a promotional tool; selling the book in bulk to customers outside the book industry; and granting the right to us part of the text to promote the book.
Subsidiary rights include things like television and feature film rights, foreign rights, first- and second-serial rights to excerpt the book before publication, translation rights, rights to produce abridged, unabridged and dramatized audio and video versions of your book, merchandising rights, and software rights (including the now popular phone “apps”). If your book has potential for subsidiary rights, you might want to include a list of them in your proposal with a short description.
Spin-offs are other books you might write as follow-ups. Could your book be a series? Does you book naturally lead you to write books on similar or related topics? Maybe you can entice a publisher into a multi-book deal. If you think so, list these follow-up or book series ideas in this section with a 50-word or less pitch for each.
Having subsidiary rights or spin-offs to sell shows you are a good business person and more than a one-book author. This can make you more enticing or appealing to a publisher and help you sell your book idea.