Unlike fiction, in which writers are asked to either submit a sample of their writing or a full manuscript, nonfiction writers are required to submit a proposal. Proposals typically run about 25 pages. They contain an overview, a detailed table of contents, a bio of the author, a business plan, a competitive title analysis showing which similar books are already on the market and why yours is better, and sample chapters. The proposal is essentially a quick guide to your book that will enable a publisher to decide whether it is worth their time and effort, so make sure you spend time and effort writing your proposal.
For detailed information on how to write a proposal read Jane Friedman's excellent article: Start Here: How to Write a Book Proposal.
For more nonfiction publishers see: 22 Cookbook Publishers Accepting Unagented Manuscripts. Many of these publishing houses accept other nonfiction titles as well.
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Allworth Press publishes business and self-help information for the general public and creative professionals. It is now owned by Skyhorse. Read their submission guidelines here. Seeking: Graphic Design, Business, Performing Arts, Interior Design, Art, Theater, Web Design, Book Arts, Photography, Crafts.
Andrews McMeel Publishing is the country's premier calendar publisher. Its core publication categories include: inspiration, middle grade children's books, comics and humor, puzzles and games, inspiration and gift, and comics for middle grade children. Interestingly, they also publish poetry. See submission guidelines HERE.
Barricade Books publishes quality non-fiction manuscripts--preferably that lean toward the controversial. Send an outline, one or two chapters, and a self-addressed stamped envelope (SASE) to Carole Stuart, Barricade Books, 2037 Lemoine Avenue, Fort Lee, NJ 07024. No email submissions.
Ben Bella publishes niche market books, works by celebrities and experts in their fields, pop culture books, and anything that is associated with a brand. Prospective authors should send a pitch.
Career Press, Inc. publishes quality, nonfiction books for adult readers seeking practical information to improve themselves in careers, college, finance, parenting, retirement, spirituality, and other related topics. Read submission policy. Seeking: Business, Career, Job Search, HR & Work Place Issues, College Preparation, Small Business/Entrepreneurship, Motivation/Self-Help, Management, Marketing/Sales, Negotiation, Study Aids, and more.
Free Spirit Publishing. "Our mission is to provide children and teens with the tools they need to overcome challenges and make a difference in the world. We publish high-quality nonfiction books and learning materials for children and teens, parents, educators, counselors, and others who live and work with young people."
Greystone Press. "We pursue high-quality non-fiction books about nature and the environment, travel and adventure, health, and current issues. We do not publish poetry or fiction." Read submission requirements here.
Gryphon House, Inc. publishes books that help teachers and parents enrich the lives of children from birth through age eight. They do not accept children's books. Seeking: Educational resource books for parents and teachers aimed at young children. Read submission policy.
Haymarket Books. "We are interested in manuscripts that are accessible to a wide range of progressive and radical political activists, while also being useful to an academic audience. We are not accepting fiction submissions at this time." Read submission guidelines here.
Hohm Press is committed to publishing books that provide readers with alternatives to the materialistic values of the current culture and promote self-awareness, the recognition of interdependence and compassion. Their subject areas include religious studies, natural health, parenting, women’s issues, the arts and poetry. Read submission guidelines here.
Menasha Ridge Press and its sister company, Wilderness Press, publish primarily books on adventure, nature, and wilderness sports activities (excluding hunting and fishing). Read submission policy.
New Internationalist is a multi-award winning, independent, non-profit media co-operative. "For over 40 years, we’ve specialized in investigative reporting, publishing our magazine and books on human rights, politics, social and environmental justice. We investigate global injustice and expose inequality. We cover stories the mainstream media sidestep and provide alternative perspectives on today’s global critical issues." Read submission policy here.
OneWorld Publications was founded in 1986 by husband and wife team Juliet Mabey and Novin Doostdar as an independent publishing house focusing on stimulating non-fiction. Located in the UK. Read guidelines here.
Osprey is a UK publisher specializing in military history. Read submission guidelines here. (Scroll down to "Proposals.")
Roaring Forties Press is a small publisher located in Berkeley, CA. They are especially interested in these kinds of nonfiction projects: General nonfiction/investigative reporting, Biographies, Travel books with a twist, Books about music, Books about art, Small-format gift books.
Rowman & Littlefield offers academic and scholarly works aimed at a professional audience. Their submission requirements include a CV and a list of potential peer reviewers.
Shambhala. "Our acquisition interests are on the topics of Buddhism, mindful living, yoga, psychology, parenting, crafting, creativity, and cooking. We do not accept proposals for fiction (children’s books excepted), poetry, exposés, end-time prophecies, channeled works, martial arts manuals, quotation books, card decks, or audio/video. Anything sent within these genres/formats will not receive a response." Read guidelines here.
Skyhorse publishes a broad range of nonfiction titles. They only accept submissions that fall into their categories, so make sure you consult their list before submitting. See submission requirements here.
The New Press is a non-profit independent publisher focusing on contemporary social issues, with an emphasis on race relations, women's issues, immigration, human rights, labor and popular economics, and the media; education reform and alternative teaching materials; cultural criticisms; art and art education; international literature; and law and legal studies. The Press has also taken a leading role in publishing a wide range of new work in African American, Asian American, Latino, gay and lesbian, and Native American studies, as well as work by and about other minority groups. They are very selective.
Ulysses Press is a small house focusing on niche markets. Genres they publish include Cleanse, Arts and Crafts, Coloring, Gifty Grabs, Fashion and Beauty, Healthy Eating, Krav Maga, Mmm Bites, Pop Culture, Prepping (for the apocalypse), Fitness, Special Diets, Trivia, Working Out, Rehab and Injury Prevention.