The Quarto Publishing Group is an international publishing house known for its illustrated books. They publish most of their work through a number of niche imprints each with their own focus. All of their US imprints are distributed by Hachette.
Their imprints are all nonfiction. They publish a lot of cookbooks and gift books. They also have imprints covering almost any nonfiction topic you can think of, including children’s nonfiction, parenting, vehicles and architecture.
This is what their website has to say about all their imprints:
Each of our imprints has its own editorial focus and fits into one of the categories below. To ensure that your book proposal winds up in the right hands, please take a moment to review each category to determine where your book best fits. Submitting to the category will send your idea to multiple imprints. If your book idea fits into our focus areas we will contact you for more details. Please bear in mind that we receive a large number of unsolicited manuscripts, so our response time may vary and we ask for your patience.
Their submission guidelines are very specific so please review them carefully before submitting. You can read the full guidelines here.
Once you have carefully reviewed their guidelines you should start composing (or editing) your book proposal.
Reviewing the catalog of the imprint you are planning to submit to is always a good idea.