Vanity Publishing
This is a concept used to describe a form of self-publishing. Vanity publishing refers to a situation where the author pays for the cost of book production. This is different from conventional publishing where the publisher pays the author for the content. A vanity publisher is a company that helps authors to self-publish their books. They collect upfront payments and embark on the production of books with their expertise and professional input in pre-production, production and post-production (marketing) strategies. But in self-publishing, the author does the production supervision directly, and cuts costs by so doing. The author personally hires individual professionals (designer, editor, production company etc.) required at each stage of the work which may involve people from different establishments.
Publishing companies prefer this business arrangement especially where the book is unlikely to sell many copies to recoup the cost of publication. Vanity publishing is also a kind of self publishing but the term sounds derogatory due to the perception that a publisher is not willing to pay for the work probably because it is sub-standard. So the term “self publishing” is preferable. It could be that the publication is in a niche area and the publisher might not want to take the risk by experimenting with publication cost no one is sure might be recouped.
Vanity publishers are often contracted where the author feels they do not have the time or inclination to do the work directly. Rather the author prefers to get someone who knows the job to handle the publishing work. That is how the vanity publisher gets involved in assisting authors to self-publish their works. The vanity publishers understand the process, have the vendors, and know what books need to be ready for publishing.