It’s not any one person. It’s not any one coach. It’s the team. Brian McBride
What is true in sports is also true in writing. Becoming a published writer involves assembling a team of talented individuals who will help you write the best book possible for your readers. Here are seven key members of a writer’s team and the roles they play to help a book succeed:
1. Beta Readers – A beta reader is someone who will read and critique the three chapters of your book that you will include in your book proposal if you are writing nonfiction or the entire manuscript if you are writing fiction. You will use this feedback to improve your manuscript before sending it to an literary agent. Choose a person who loves books, belongs to your target audience, and understands how to give feedback on the big picture of your writing instead of bogging down circling typos.
Give your beta readers a time frame for completing their critique and clarify that your manuscript is confidential and should not be shared with others. A beta reader who is also a writer or who understands the publishing industry is ideal. Send your manuscript to multiple beta readers and pay close attention to feedback that is echoed by more than one beta reader.
2. Agent – Your literary agent presents your book to publishers and negotiates the sale. However, your literary agent often provides guidance and editorial suggestions before your book proposal is submitted. He or she knows the industry, so take the advice. After your book is published, your literary agent can provide marketing advice and help you develop your writing career.
3. Editor – Your editor helps you polish your manuscript to its final form, while also guiding you through the entire publication process – title selection, cover art, book design, copy editing, and choice of reviewers.
4. Reviewers – You will encounter three types of reviewers in the traditional book publishing process. The first set of reviewers, selected by your editor, provide feedback on your manuscript. You can take or disregard their suggestions when writing your final draft. However, their insights help you see your book with fresh eyes and learn how your readers might respond to certain passages. The second set of reviewers read the final manuscript and write short reviews for inclusion on the back cover of your book. You select these reviewers with input from your editor. The last set of reviewers are the readers who bought your book and decided to review it on Goodreads, Amazon, a bookstore website, or their blog. All reviewers are essential for the success of the book and the development of your writing career.
5. Marketing Director – Your marketing director will help your book find its way to readers. He or she will coordinate ad placement, mailing copies of your book to key influencers, and the work of a team of publicists. Touch base with your marketing director if you see a valuable opportunity for getting the word out about your book. Coordinate your author efforts with the marketing plan your publisher develops for your book.
6. Publicists – Publicists may specialize in broadcast, publications or online publicity. If you are fortunate to have a publisher that has a team of publicists working to promote your book, they will arrange radio and podcast interviews and connect you with print and online opportunities to introduce readers to your book.
7. Key Influencers – Key influencers are the individuals who will receive an early copy of your book from your publisher. These individuals should connect with segments of your target audience and be able to create positive buzz about your book. Choose influencers across a wide geographical area and with characteristics that represent the breadth of your likely readers.
Other individuals may join the team to help you create a valuable book for your readers, but these seven key team members make up the core of your team as a writer. Appreciate the expertise that each team member brings, and build a good working relationship with all of them.
How has working with a team enhanced your writing career?
WordServe Water Cooler 
Someone who encourages you (friend, Spouse, family) is also a part of the team.
Yes, you could add many others to the list. The post focused on the core professional team members a writer is likely to encounter when writing a book for a traditional publisher.